Hi Andrey,

Some more comments...

On Tue October 23 2012 20:44:31 Andrey Smirnov wrote:
> This commit adds a driver that exposes all the radio related
> functionality of the Si476x series of chips via the V4L2 subsystem.
> 
> Signed-off-by: Andrey Smirnov <andrey.smir...@convergeddevices.net>
> ---
>  drivers/media/radio/Kconfig        |   17 +
>  drivers/media/radio/Makefile       |    1 +
>  drivers/media/radio/radio-si476x.c | 1549 
> ++++++++++++++++++++++++++++++++++++
>  3 files changed, 1567 insertions(+)
>  create mode 100644 drivers/media/radio/radio-si476x.c
> 

<cut>

> diff --git a/drivers/media/radio/radio-si476x.c 
> b/drivers/media/radio/radio-si476x.c
> new file mode 100644
> index 0000000..c8fa90f
> --- /dev/null
> +++ b/drivers/media/radio/radio-si476x.c
> @@ -0,0 +1,1549 @@
> +#include <linux/module.h>
> +#include <linux/delay.h>
> +#include <linux/interrupt.h>
> +#include <linux/slab.h>
> +#include <linux/atomic.h>
> +#include <linux/videodev2.h>
> +#include <linux/mutex.h>
> +#include <linux/debugfs.h>
> +#include <media/v4l2-common.h>
> +#include <media/v4l2-ioctl.h>
> +#include <media/v4l2-ctrls.h>
> +#include <media/v4l2-event.h>
> +#include <media/v4l2-device.h>
> +
> +
> +#include <linux/mfd/si476x-core.h>
> +
> +#define FM_FREQ_RANGE_LOW   64000000
> +#define FM_FREQ_RANGE_HIGH 108000000
> +
> +#define AM_FREQ_RANGE_LOW    520000
> +#define AM_FREQ_RANGE_HIGH 30000000
> +
> +#define PWRLINEFLTR (1 << 8)
> +
> +#define FREQ_MUL (10000000 / 625)
> +
> +#define SI476X_PHDIV_STATUS_LINK_LOCKED(status) (0b10000000 & (status))
> +
> +#define DRIVER_NAME "si476x-radio"
> +#define DRIVER_CARD "SI476x AM/FM Receiver"
> +
> +enum si476x_freq_bands {
> +     SI476X_BAND_FM,
> +     SI476X_BAND_AM,
> +};
> +
> +static const struct v4l2_frequency_band si476x_bands[] = {
> +     [SI476X_BAND_FM] = {
> +             .type           = V4L2_TUNER_RADIO,
> +             .index          = SI476X_BAND_FM,
> +             .capability     = V4L2_TUNER_CAP_LOW
> +             | V4L2_TUNER_CAP_STEREO
> +             | V4L2_TUNER_CAP_RDS
> +             | V4L2_TUNER_CAP_RDS_BLOCK_IO
> +             | V4L2_TUNER_CAP_FREQ_BANDS,
> +             .rangelow       =  64 * FREQ_MUL,
> +             .rangehigh      = 108 * FREQ_MUL,
> +             .modulation     = V4L2_BAND_MODULATION_FM,
> +     },
> +     [SI476X_BAND_AM] = {
> +             .type           = V4L2_TUNER_RADIO,
> +             .index          = SI476X_BAND_AM,
> +             .capability     = V4L2_TUNER_CAP_LOW | 
> V4L2_TUNER_CAP_FREQ_BANDS,
> +             .rangelow       = 0.52 * FREQ_MUL,
> +             .rangehigh      = 30 * FREQ_MUL,
> +             .modulation     = V4L2_BAND_MODULATION_AM,
> +     },
> +};
> +
> +static inline bool si476x_radio_freq_is_inside_of_the_band(u32 freq, int 
> band)
> +{
> +     return freq >= si476x_bands[band].rangelow &&
> +             freq <= si476x_bands[band].rangehigh;
> +}
> +
> +static inline bool si476x_radio_range_is_inside_of_the_band(u32 low, u32 
> high, int band)
> +{
> +     return low  >= si476x_bands[band].rangelow &&
> +             high <= si476x_bands[band].rangehigh;
> +}
> +
> +#define PRIVATE_CTL_IDX(x) (x - V4L2_CID_PRIVATE_BASE)

No. The new control IDs need to be added to include/uapi/linux/v4l2-controls.h
with unique IDs. V4L2_CID_PRIVATE_BASE must not be used anymore for new 
controls.

Since Halli Manjunatha hasn't worked on a new version of his patch with the new
fm controls it might be something you want to take on (I'm referring to the FM 
RX
control class).

> +
> +static int si476x_radio_s_ctrl(struct v4l2_ctrl *ctrl);
> +static int si476x_radio_g_volatile_ctrl(struct v4l2_ctrl *ctrl);
> +
> +static const char * const deemphasis[] = {
> +     "75 us",
> +     "50 us",
> +};
> +
> +enum phase_diversity_modes_idx {
> +     SI476X_IDX_PHDIV_DISABLED,
> +     SI476X_IDX_PHDIV_PRIMARY_COMBINING,
> +     SI476X_IDX_PHDIV_PRIMARY_ANTENNA,
> +     SI476X_IDX_PHDIV_SECONDARY_ANTENNA,
> +     SI476X_IDX_PHDIV_SECONDARY_COMBINING,
> +};
> +
> +static const char * const phase_diversity_modes[] = {
> +     [SI476X_IDX_PHDIV_DISABLED]             = "disabled",
> +     [SI476X_IDX_PHDIV_PRIMARY_COMBINING]    = "primary w/secondary",
> +     [SI476X_IDX_PHDIV_PRIMARY_ANTENNA]      = "primary(primary antenna)",
> +     [SI476X_IDX_PHDIV_SECONDARY_ANTENNA]    = "primary(seconadary antenna)",
> +     [SI476X_IDX_PHDIV_SECONDARY_COMBINING]  = "secondary w/primary",
> +};
> +
> +static inline enum phase_diversity_modes_idx
> +si476x_phase_diversity_mode_to_idx(enum si476x_phase_diversity_mode mode)
> +{
> +     switch (mode) {
> +     default:                /* FALLTHROUGH */
> +     case SI476X_PHDIV_DISABLED:
> +             return SI476X_IDX_PHDIV_DISABLED;
> +     case SI476X_PHDIV_PRIMARY_COMBINING:
> +             return SI476X_IDX_PHDIV_PRIMARY_COMBINING;
> +     case SI476X_PHDIV_PRIMARY_ANTENNA:
> +             return SI476X_IDX_PHDIV_PRIMARY_ANTENNA;
> +     case SI476X_PHDIV_SECONDARY_ANTENNA:
> +             return SI476X_IDX_PHDIV_SECONDARY_ANTENNA;
> +     case SI476X_PHDIV_SECONDARY_COMBINING:
> +             return SI476X_IDX_PHDIV_SECONDARY_COMBINING;
> +     }
> +}
> +
> +static inline enum si476x_phase_diversity_mode
> +si476x_phase_diversity_idx_to_mode(enum phase_diversity_modes_idx idx)
> +{
> +     static const int idx_to_value[] = {
> +             [SI476X_IDX_PHDIV_DISABLED]             = SI476X_PHDIV_DISABLED,
> +             [SI476X_IDX_PHDIV_PRIMARY_COMBINING]    = 
> SI476X_PHDIV_PRIMARY_COMBINING,
> +             [SI476X_IDX_PHDIV_PRIMARY_ANTENNA]      = 
> SI476X_PHDIV_PRIMARY_ANTENNA,
> +             [SI476X_IDX_PHDIV_SECONDARY_ANTENNA]    = 
> SI476X_PHDIV_SECONDARY_ANTENNA,
> +             [SI476X_IDX_PHDIV_SECONDARY_COMBINING]  = 
> SI476X_PHDIV_SECONDARY_COMBINING,
> +     };
> +
> +     return idx_to_value[idx];
> +}
> +
> +static const struct v4l2_ctrl_ops si476x_ctrl_ops = {
> +     .g_volatile_ctrl        = si476x_radio_g_volatile_ctrl,
> +     .s_ctrl                 = si476x_radio_s_ctrl,
> +};
> +
> +
> +enum si476x_ctrl_idx {
> +     SI476X_IDX_RSSI_THRESHOLD,
> +     SI476X_IDX_SNR_THRESHOLD,
> +     SI476X_IDX_MAX_TUNE_ERROR,
> +     SI476X_IDX_HARMONICS_COUNT,
> +     SI476X_IDX_DEEMPHASIS,
> +     SI476X_IDX_RDS_RECEPTION,
> +     SI476X_IDX_DIVERSITY_MODE,
> +     SI476X_IDX_INTERCHIP_LINK,
> +};
> +
> +static struct v4l2_ctrl_config si476x_ctrls[] = {
> +     /*
> +        Tuning parameters
> +        'max tune errors' is shared for both AM/FM mode of operation
> +     */
> +     [SI476X_IDX_RSSI_THRESHOLD] = {
> +             .ops    = &si476x_ctrl_ops,
> +             .id     = SI476X_CID_RSSI_THRESHOLD,
> +             .name   = "valid rssi threshold",

The names of the controls should be capitilized, just like a title of a book.

So this should become "Valid RSSI Threshold", etc.

> +             .type   = V4L2_CTRL_TYPE_INTEGER,
> +             .min    = -128,
> +             .max    = 127,
> +             .step   = 1,
> +     },
> +     [SI476X_IDX_SNR_THRESHOLD] = {
> +             .ops    = &si476x_ctrl_ops,
> +             .id     = SI476X_CID_SNR_THRESHOLD,
> +             .type   = V4L2_CTRL_TYPE_INTEGER,
> +             .name   = "valid snr threshold",
> +             .min    = -128,
> +             .max    = 127,
> +             .step   = 1,
> +     },
> +     [SI476X_IDX_MAX_TUNE_ERROR] = {
> +             .ops    = &si476x_ctrl_ops,
> +             .id     = SI476X_CID_MAX_TUNE_ERROR,
> +             .type   = V4L2_CTRL_TYPE_INTEGER,
> +             .name   = "max tune errors",
> +             .min    = 0,
> +             .max    = 126 * 2,
> +             .step   = 2,
> +     },
> +     /*
> +        Region specific parameters
> +     */
> +     [SI476X_IDX_HARMONICS_COUNT] = {
> +             .ops    = &si476x_ctrl_ops,
> +             .id     = SI476X_CID_HARMONICS_COUNT,
> +             .type   = V4L2_CTRL_TYPE_INTEGER,
> +
> +             .name   = "count of harmonics to reject",
> +             .min    = 0,
> +             .max    = 20,
> +             .step   = 1,
> +     },
> +     [SI476X_IDX_DEEMPHASIS] = {
> +             .ops    = &si476x_ctrl_ops,
> +             .id     = SI476X_CID_DEEMPHASIS,
> +             .type   = V4L2_CTRL_TYPE_MENU,
> +             .name   = "de-emphassis",
> +             .qmenu  = deemphasis,
> +             .min    = 0,
> +             .max    = ARRAY_SIZE(deemphasis) - 1,
> +             .def    = 0,
> +     },
> +     [SI476X_IDX_RDS_RECEPTION] = {
> +             .ops    = &si476x_ctrl_ops,
> +             .id     = SI476X_CID_RDS_RECEPTION,
> +             .type   = V4L2_CTRL_TYPE_BOOLEAN,
> +             .name   = "rds",

This name is too vague. Something like "RDS Reception" perhaps?

> +             .min    = 0,
> +             .max    = 1,
> +             .step   = 1,
> +     },
> +     [SI476X_IDX_DIVERSITY_MODE] = {
> +             .ops    = &si476x_ctrl_ops,
> +             .id     = SI476X_CID_DIVERSITY_MODE,
> +             .type   = V4L2_CTRL_TYPE_MENU,
> +             .name   = "phase diversity mode",
> +             .qmenu  = phase_diversity_modes,
> +             .min    = 0,
> +             .max    = ARRAY_SIZE(phase_diversity_modes) - 1,
> +     },
> +     [SI476X_IDX_INTERCHIP_LINK] = {
> +             .ops    = &si476x_ctrl_ops,
> +             .id     = SI476X_CID_INTERCHIP_LINK,
> +             .type   = V4L2_CTRL_TYPE_BOOLEAN,
> +             .flags  = V4L2_CTRL_FLAG_READ_ONLY | V4L2_CTRL_FLAG_VOLATILE,
> +             .name   = "inter-chip link",
> +             .min    = 0,
> +             .max    = 1,
> +             .step   = 1,

Note that all these controls need to be documented as well.

> +     },
> +};
> +
> +struct si476x_radio;
> +
> +/**
> + * struct si476x_radio_ops - vtable of tuner functions
> + *
> + * This table holds pointers to functions implementing particular
> + * operations depending on the mode in which the tuner chip was
> + * configured to start in. If the function is not supported
> + * corresponding element is set to #NULL.
> + *
> + * @tune_freq: Tune chip to a specific frequency
> + * @seek_start: Star station seeking
> + * @rsq_status: Get Recieved Signal Quality(RSQ) status
> + * @rds_blckcnt: Get recived RDS blocks count
> + * @phase_diversity: Change phase diversity mode of the tuner
> + * @phase_div_status: Get phase diversity mode status
> + * @acf_status: Get the status of Automatically Controlled
> + * Features(ACF)
> + * @agc_status: Get Automatic Gain Control(AGC) status
> + */
> +struct si476x_radio_ops {
> +     int (*tune_freq)(struct si476x_core *, struct si476x_tune_freq_args *);
> +     int (*seek_start)(struct si476x_core *, bool, bool);
> +     int (*rsq_status)(struct si476x_core *, struct si476x_rsq_status_args *,
> +                       struct si476x_rsq_status_report *);
> +     int (*rds_blckcnt)(struct si476x_core *, bool,
> +                        struct si476x_rds_blockcount_report *);
> +
> +     int (*phase_diversity)(struct si476x_core *,
> +                            enum si476x_phase_diversity_mode);
> +     int (*phase_div_status)(struct si476x_core *);
> +     int (*acf_status)(struct si476x_core *,
> +                       struct si476x_acf_status_report *);
> +     int (*agc_status)(struct si476x_core *,
> +                       struct si476x_agc_status_report *);
> +};
> +
> +/**
> + * struct si476x_radio - radio device
> + *
> + * @core: Pointer to underlying core device
> + * @videodev: Pointer to video device created by V4L2 subsystem
> + * @ops: Vtable of functions. See struct si476x_radio_ops for details
> + * @kref: Reference counter
> + * @core_lock: An r/w semaphore to brebvent the deletion of underlying
> + * core structure is the radio device is being used
> + */
> +struct si476x_radio {
> +     struct v4l2_device v4l2dev;
> +     struct video_device videodev;
> +     struct v4l2_ctrl_handler ctrl_handler;
> +
> +     struct si476x_core  *core;
> +     /* This field should not be accesses unless core lock is held */
> +     const struct si476x_radio_ops *ops;
> +
> +     struct dentry   *debugfs;
> +     u32 audmode;
> +};
> +
> +static inline struct si476x_radio *v4l2_dev_to_radio(struct v4l2_device *d)
> +{
> +     return container_of(d, struct si476x_radio, v4l2dev);
> +}
> +
> +static inline struct si476x_radio *v4l2_ctrl_handler_to_radio(struct 
> v4l2_ctrl_handler *d)
> +{
> +     return container_of(d, struct si476x_radio, ctrl_handler);
> +}
> +
> +/*
> + * si476x_vidioc_querycap - query device capabilities
> + */
> +static int si476x_radio_querycap(struct file *file, void *priv,
> +                              struct v4l2_capability *capability)
> +{
> +     struct si476x_radio *radio = video_drvdata(file);
> +
> +     strlcpy(capability->driver, radio->v4l2dev.name,
> +             sizeof(capability->driver));
> +     strlcpy(capability->card,   DRIVER_CARD, sizeof(capability->card));
> +     snprintf(capability->bus_info, sizeof(capability->bus_info),
> +              "platform:%s", radio->v4l2dev.name);
> +
> +     capability->device_caps = V4L2_CAP_TUNER
> +             | V4L2_CAP_RADIO
> +             | V4L2_CAP_HW_FREQ_SEEK;
> +
> +     si476x_core_lock(radio->core);
> +     if (!si476x_core_is_a_secondary_tuner(radio->core))
> +             capability->device_caps |= V4L2_CAP_RDS_CAPTURE
> +                     | V4L2_CAP_READWRITE;
> +     si476x_core_unlock(radio->core);
> +
> +     capability->capabilities = capability->device_caps | 
> V4L2_CAP_DEVICE_CAPS;
> +     return 0;
> +}
> +
> +static int si476x_radio_enum_freq_bands(struct file *file, void *priv,
> +                                     struct v4l2_frequency_band *band)
> +{
> +     int err;
> +     struct si476x_radio *radio = video_drvdata(file);
> +
> +     if (band->tuner != 0)
> +             return -EINVAL;
> +
> +     switch (radio->core->chip_id) {
> +             /* AM/FM tuners -- all bands are supported */
> +     case SI476X_CHIP_SI4761:
> +     case SI476X_CHIP_SI4764:
> +             if (band->index < ARRAY_SIZE(si476x_bands)) {
> +                     *band = si476x_bands[band->index];
> +                     err = 0;
> +             } else {
> +                     err = -EINVAL;
> +             }
> +             break;
> +             /* FM companion tuner chips -- only FM bands are
> +              * supported */
> +     case SI476X_CHIP_SI4768:
> +             if (band->index == SI476X_BAND_FM) {
> +                     *band = si476x_bands[band->index];
> +                     err = 0;
> +             } else {
> +                     err = -EINVAL;
> +             }
> +             break;
> +     default:
> +             err = -EINVAL;
> +     }
> +
> +     return err;
> +}
> +
> +static int si476x_radio_g_tuner(struct file *file, void *priv,
> +                             struct v4l2_tuner *tuner)
> +{
> +     int err;
> +     struct si476x_rsq_status_report report;
> +     struct si476x_radio *radio = video_drvdata(file);
> +
> +     struct si476x_rsq_status_args args = {
> +             .primary        = false,
> +             .rsqack         = false,
> +             .attune         = false,
> +             .cancel         = false,
> +             .stcack         = false,
> +     };
> +
> +     if (tuner->index != 0)
> +             return -EINVAL;
> +
> +     tuner->type       = V4L2_TUNER_RADIO;
> +     tuner->capability = V4L2_TUNER_CAP_LOW /* Measure frequencies
> +                                              * in multiples of
> +                                              * 62.5 Hz */
> +             | V4L2_TUNER_CAP_STEREO
> +             | V4L2_TUNER_CAP_HWSEEK_BOUNDED
> +             | V4L2_TUNER_CAP_HWSEEK_WRAP
> +             | V4L2_TUNER_CAP_HWSEEK_PROG_LIM;
> +
> +     si476x_core_lock(radio->core);
> +
> +     if (si476x_core_is_a_secondary_tuner(radio->core)) {
> +             strlcpy(tuner->name, "FM (secondary)", sizeof(tuner->name));
> +             tuner->rxsubchans = 0;
> +             tuner->rangelow = si476x_bands[SI476X_BAND_FM].rangelow;
> +     } else if (si476x_core_has_am(radio->core)) {
> +             if (si476x_core_is_a_primary_tuner(radio->core))
> +                     strlcpy(tuner->name, "AM/FM (primary)", 
> sizeof(tuner->name));
> +             else
> +                     strlcpy(tuner->name, "AM/FM", sizeof(tuner->name));
> +
> +             tuner->rxsubchans = V4L2_TUNER_SUB_MONO | V4L2_TUNER_SUB_STEREO
> +                     | V4L2_TUNER_SUB_RDS;
> +             tuner->capability |= V4L2_TUNER_CAP_RDS
> +                     | V4L2_TUNER_CAP_RDS_BLOCK_IO
> +                     | V4L2_TUNER_CAP_FREQ_BANDS;
> +
> +             tuner->rangelow = si476x_bands[SI476X_BAND_AM].rangelow;
> +     } else {
> +             strlcpy(tuner->name, "FM", sizeof(tuner->name));
> +             tuner->rxsubchans = V4L2_TUNER_SUB_RDS;
> +             tuner->capability |= V4L2_TUNER_CAP_RDS
> +                     | V4L2_TUNER_CAP_RDS_BLOCK_IO
> +                     | V4L2_TUNER_CAP_FREQ_BANDS;
> +             tuner->rangelow = si476x_bands[SI476X_BAND_FM].rangelow;
> +     }
> +
> +     tuner->audmode = radio->audmode;
> +
> +     tuner->afc = 1;
> +     tuner->rangehigh = si476x_bands[SI476X_BAND_FM].rangehigh;
> +
> +     err = radio->ops->rsq_status(radio->core,
> +                                  &args, &report);
> +     if (err < 0) {
> +             tuner->signal = 0;
> +     } else {
> +             /*
> +              * tuner->signal value range: 0x0000 .. 0xFFFF,
> +              * report.rssi: -128 .. 127
> +              */
> +             tuner->signal = (report.rssi + 128) * 257;
> +     }
> +     si476x_core_unlock(radio->core);
> +
> +     return err;
> +}
> +
> +static int si476x_radio_s_tuner(struct file *file, void *priv,
> +                             struct v4l2_tuner *tuner)
> +{
> +     struct si476x_radio *radio = video_drvdata(file);
> +
> +     if (tuner->index != 0)
> +             return -EINVAL;
> +
> +     if (tuner->audmode == V4L2_TUNER_MODE_MONO ||
> +         tuner->audmode == V4L2_TUNER_MODE_STEREO)
> +             radio->audmode = tuner->audmode;
> +     else
> +             radio->audmode = V4L2_TUNER_MODE_STEREO;
> +
> +     return 0;
> +}
> +
> +static int si476x_radio_init_vtable(struct si476x_radio *radio, enum 
> si476x_func func)
> +{
> +     static const struct si476x_radio_ops fm_ops = {
> +             .tune_freq              = si476x_core_cmd_fm_tune_freq,
> +             .seek_start             = si476x_core_cmd_fm_seek_start,
> +             .rsq_status             = si476x_core_cmd_fm_rsq_status,
> +             .rds_blckcnt            = si476x_core_cmd_fm_rds_blockcount,
> +             .phase_diversity        = si476x_core_cmd_fm_phase_diversity,
> +             .phase_div_status       = si476x_core_cmd_fm_phase_div_status,
> +             .acf_status             = si476x_core_cmd_fm_acf_status,
> +             .agc_status             = si476x_core_cmd_agc_status,
> +     };
> +
> +     static const struct si476x_radio_ops am_ops = {
> +             .tune_freq              = si476x_core_cmd_am_tune_freq,
> +             .seek_start             = si476x_core_cmd_am_seek_start,
> +             .rsq_status             = si476x_core_cmd_am_rsq_status,
> +             .rds_blckcnt            = NULL,
> +             .phase_diversity        = NULL,
> +             .phase_div_status       = NULL,
> +             .acf_status             = si476x_core_cmd_am_acf_status,
> +             .agc_status             = NULL,
> +     };
> +
> +     switch (func) {
> +     case SI476X_FUNC_FM_RECEIVER:
> +             radio->ops = &fm_ops;
> +             return 0;
> +
> +     case SI476X_FUNC_AM_RECEIVER:
> +             radio->ops = &am_ops;
> +             return 0;
> +     default:
> +             WARN(1, "Unexpected tuner function value\n");
> +             return -EINVAL;
> +     }
> +}
> +
> +static int si476x_radio_pretune(struct si476x_radio *radio, enum si476x_func 
> func)
> +{
> +     int retval;
> +
> +     struct si476x_tune_freq_args args = {
> +             .zifsr          = false,
> +             .hd             = false,
> +             .injside        = SI476X_INJSIDE_AUTO,
> +             .tunemode       = SI476X_TM_VALIDATED_NORMAL_TUNE,
> +             .smoothmetrics  = SI476X_SM_INITIALIZE_AUDIO,
> +             .antcap         = 0,
> +     };
> +
> +     switch (func) {
> +     case SI476X_FUNC_FM_RECEIVER:
> +             args.freq = v4l2_to_si476x(radio->core,
> +                                        92 * FREQ_MUL);
> +             retval = radio->ops->tune_freq(radio->core, &args);
> +             break;
> +     case SI476X_FUNC_AM_RECEIVER:
> +             args.freq = v4l2_to_si476x(radio->core,
> +                                        0.6 * FREQ_MUL);
> +             retval = radio->ops->tune_freq(radio->core, &args);
> +             break;
> +     default:
> +             WARN(1, "Unexpected tuner function value\n");
> +             retval = -EINVAL;
> +     }
> +
> +     return retval;
> +}
> +static int si476x_radio_do_post_powerup_init(struct si476x_radio *radio, 
> enum si476x_func func)
> +{
> +     int err;
> +
> +     /* regcache_mark_dirty(radio->core->regmap); */
> +     err = regcache_sync_region(radio->core->regmap,
> +                                SI476X_PROP_DIGITAL_IO_INPUT_SAMPLE_RATE,
> +                                SI476X_PROP_DIGITAL_IO_OUTPUT_FORMAT);
> +             if (err < 0)
> +                     return err;
> +
> +     err = regcache_sync_region(radio->core->regmap,
> +                                SI476X_PROP_AUDIO_DEEMPHASIS,
> +                                SI476X_PROP_AUDIO_PWR_LINE_FILTER);
> +     if (err < 0)
> +             return err;
> +
> +     err = regcache_sync_region(radio->core->regmap,
> +                                SI476X_PROP_INT_CTL_ENABLE,
> +                                SI476X_PROP_INT_CTL_ENABLE);
> +     if (err < 0)
> +             return err;
> +
> +     /*
> +      * Is there any point in restoring SNR and the like
> +      * when switching between AM/FM?
> +      */
> +     err = regcache_sync_region(radio->core->regmap,
> +                                SI476X_PROP_VALID_MAX_TUNE_ERROR,
> +                                SI476X_PROP_VALID_MAX_TUNE_ERROR);
> +     if (err < 0)
> +             return err;
> +
> +     err = regcache_sync_region(radio->core->regmap,
> +                                SI476X_PROP_VALID_SNR_THRESHOLD,
> +                                SI476X_PROP_VALID_RSSI_THRESHOLD);
> +     if (err < 0)
> +             return err;
> +
> +     if (func == SI476X_FUNC_FM_RECEIVER) {
> +             if (si476x_core_has_diversity(radio->core)) {
> +                     err = si476x_core_cmd_fm_phase_diversity(radio->core,
> +                                                              
> radio->core->diversity_mode);
> +                     if (err < 0)
> +                             return err;
> +             }
> +
> +             err = regcache_sync_region(radio->core->regmap,
> +                                        SI476X_PROP_FM_RDS_INTERRUPT_SOURCE,
> +                                        SI476X_PROP_FM_RDS_CONFIG);
> +             if (err < 0)
> +                     return err;
> +     }
> +
> +     return si476x_radio_init_vtable(radio, func);
> +
> +}
> +
> +static int si476x_radio_change_func(struct si476x_radio *radio, enum 
> si476x_func func)
> +{
> +     int err;
> +     bool soft;
> +     /*
> +      * Since power/up down is a very time consuming operation,
> +      * try to avoid doing it if the requested mode matches the one
> +      * the tuner is in
> +      */
> +     if (func == radio->core->power_up_parameters.func)
> +             return 0;
> +
> +     soft = true;
> +     err = si476x_core_stop(radio->core, soft);
> +     if (err < 0) {
> +             /*
> +              * OK, if the chip does not want to play nice let's
> +              * try to reset it in more brutal way
> +              */
> +             soft = false;
> +             err = si476x_core_stop(radio->core, soft);
> +             if (err < 0)
> +                     return err;
> +     }
> +     /*
> +       Set the desired radio tuner function
> +      */
> +     radio->core->power_up_parameters.func = func;
> +
> +     err = si476x_core_start(radio->core, soft);
> +     if (err < 0)
> +             return err;
> +
> +     /*
> +      * No need to do the rest of manipulations for the bootlader
> +      * mode
> +      */
> +     if (func != SI476X_FUNC_FM_RECEIVER &&
> +         func != SI476X_FUNC_AM_RECEIVER)
> +             return err;
> +
> +     return si476x_radio_do_post_powerup_init(radio, func);
> +}
> +
> +static int si476x_radio_g_frequency(struct file *file, void *priv,
> +                           struct v4l2_frequency *f)
> +{
> +     int err;
> +     struct si476x_radio *radio = video_drvdata(file);
> +
> +     if (f->tuner != 0 ||
> +         f->type  != V4L2_TUNER_RADIO)
> +             return -EINVAL;
> +
> +     si476x_core_lock(radio->core);
> +
> +     if (radio->ops->rsq_status) {
> +             struct si476x_rsq_status_report report;
> +             struct si476x_rsq_status_args   args = {
> +                     .primary        = false,
> +                     .rsqack         = false,
> +                     .attune         = true,
> +                     .cancel         = false,
> +                     .stcack         = false,
> +             };
> +
> +             err = radio->ops->rsq_status(radio->core, &args, &report);
> +             if (!err)
> +                     f->frequency = si476x_to_v4l2(radio->core,
> +                                                   report.readfreq);
> +     } else {
> +             err = -EINVAL;
> +     }
> +
> +     si476x_core_unlock(radio->core);
> +
> +     return err;
> +}
> +
> +static int si476x_radio_s_frequency(struct file *file, void *priv,
> +                                 struct v4l2_frequency *f)
> +{
> +     int err;
> +     struct si476x_tune_freq_args args;
> +     struct si476x_radio *radio = video_drvdata(file);
> +
> +     const u32 midrange = (si476x_bands[SI476X_BAND_AM].rangehigh +
> +                           si476x_bands[SI476X_BAND_FM].rangelow) / 2;
> +     const int band = (f->frequency > midrange) ? SI476X_BAND_FM : 
> SI476X_BAND_AM;
> +     const enum si476x_func func = (band == SI476X_BAND_AM) ?
> +             SI476X_FUNC_AM_RECEIVER : SI476X_FUNC_FM_RECEIVER;
> +
> +     if (f->tuner != 0 ||
> +         f->type  != V4L2_TUNER_RADIO)
> +             return -EINVAL;
> +
> +     si476x_core_lock(radio->core);
> +
> +     f->frequency = clamp(f->frequency,
> +                          si476x_bands[band].rangelow,
> +                          si476x_bands[band].rangehigh);
> +
> +     if (si476x_radio_freq_is_inside_of_the_band(f->frequency, 
> SI476X_BAND_AM) &&
> +         (!si476x_core_has_am(radio->core) || 
> si476x_core_is_a_secondary_tuner(radio->core))) {
> +             err = -EINVAL;
> +             goto unlock;
> +     }
> +
> +     err = si476x_radio_change_func(radio, func);
> +     if (err < 0)
> +             goto unlock;
> +
> +     args.zifsr              = false;
> +     args.hd                 = false;
> +     args.injside            = SI476X_INJSIDE_AUTO;
> +     args.freq               = v4l2_to_si476x(radio->core,
> +                                              f->frequency);
> +     args.tunemode           = SI476X_TM_VALIDATED_NORMAL_TUNE;
> +     args.smoothmetrics      = SI476X_SM_INITIALIZE_AUDIO;
> +     args.antcap             = 0;
> +
> +     err = radio->ops->tune_freq(radio->core, &args);
> +
> +unlock:
> +     si476x_core_unlock(radio->core);
> +     return err;
> +}
> +
> +static int si476x_radio_s_hw_freq_seek(struct file *file, void *priv,
> +                                    const struct v4l2_hw_freq_seek *seek)
> +{
> +     int err;
> +     enum si476x_func func;
> +     u32 rangelow, rangehigh;
> +     struct si476x_radio *radio = video_drvdata(file);
> +
> +     if (file->f_flags & O_NONBLOCK)
> +             return -EAGAIN;
> +
> +     if (seek->tuner != 0 ||
> +         seek->type  != V4L2_TUNER_RADIO)
> +             return -EINVAL;
> +
> +     si476x_core_lock(radio->core);
> +
> +     if(!seek->rangelow) {
> +             err = regmap_read(radio->core->regmap,
> +                               SI476X_PROP_SEEK_BAND_BOTTOM,
> +                               &rangelow);
> +             if (!err)
> +                     rangelow = si476x_to_v4l2(radio->core, rangelow);
> +             else
> +                     goto unlock;
> +     }
> +     if(!seek->rangehigh) {
> +             err = regmap_read(radio->core->regmap,
> +                               SI476X_PROP_SEEK_BAND_TOP,
> +                               &rangehigh);
> +             if (!err)
> +                     rangehigh = si476x_to_v4l2(radio->core, rangehigh);
> +             else
> +                     goto unlock;
> +     }
> +
> +     if (rangelow > rangehigh) {
> +             err = -EINVAL;
> +             goto unlock;
> +     }
> +
> +     if (si476x_radio_range_is_inside_of_the_band(rangelow, rangehigh,
> +                                                  SI476X_BAND_FM)) {
> +             func = SI476X_FUNC_FM_RECEIVER;
> +
> +     } else if (si476x_core_has_am(radio->core) &&
> +                si476x_radio_range_is_inside_of_the_band(rangelow, rangehigh,
> +                                                         SI476X_BAND_AM)) {
> +             func = SI476X_FUNC_AM_RECEIVER;
> +     } else {
> +             err = -EINVAL;
> +             goto unlock;
> +     }
> +
> +     err = si476x_radio_change_func(radio, func);
> +     if (err < 0) {
> +             goto unlock;
> +     }
> +
> +     if (seek->rangehigh) {
> +             err = regmap_write(radio->core->regmap,
> +                                SI476X_PROP_SEEK_BAND_TOP,
> +                                v4l2_to_si476x(radio->core,
> +                                               seek->rangehigh));
> +             if (err)
> +                     goto unlock;
> +     }
> +     if (seek->rangelow) {
> +             err = regmap_write(radio->core->regmap,
> +                                SI476X_PROP_SEEK_BAND_BOTTOM,
> +                                v4l2_to_si476x(radio->core,
> +                                               seek->rangelow));
> +             if (err)
> +                     goto unlock;
> +     }
> +     if (seek->spacing) {
> +             err = regmap_write(radio->core->regmap,
> +                                  SI476X_PROP_SEEK_FREQUENCY_SPACING,
> +                                  v4l2_to_si476x(radio->core,
> +                                                 seek->spacing));
> +             if (err)
> +                     goto unlock;
> +     }
> +
> +     err = radio->ops->seek_start(radio->core,
> +                                  seek->seek_upward,
> +                                  seek->wrap_around);
> +unlock:
> +     si476x_core_unlock(radio->core);
> +
> +
> +
> +     return err;
> +}
> +
> +static int si476x_radio_g_volatile_ctrl(struct v4l2_ctrl *ctrl)
> +{
> +     int retval;
> +     struct si476x_radio *radio = v4l2_ctrl_handler_to_radio(ctrl->handler);
> +
> +     si476x_core_lock(radio->core);
> +
> +     switch (ctrl->id) {
> +     case SI476X_CID_INTERCHIP_LINK:
> +             if (si476x_core_has_diversity(radio->core)) {
> +                     if (radio->ops->phase_diversity) {
> +                             retval = 
> radio->ops->phase_div_status(radio->core);
> +                             if (retval < 0)
> +                                     break;
> +
> +                             ctrl->val = 
> !!SI476X_PHDIV_STATUS_LINK_LOCKED(retval);
> +                             retval = 0;
> +                             break;
> +                     } else {
> +                             retval = -ENOTTY;

If ops->phase_diversity wasn't set, then this control shouldn't have been added
in the first place. It should never return ENOTTY.

> +                             break;
> +                     }
> +             }
> +             retval = -EINVAL;
> +             break;
> +     default:
> +             retval = -EINVAL;
> +             break;
> +     }
> +     si476x_core_unlock(radio->core);
> +     return retval;
> +
> +}
> +
> +static int si476x_radio_s_ctrl(struct v4l2_ctrl *ctrl)
> +{
> +     int retval;
> +     enum si476x_phase_diversity_mode mode;
> +     struct si476x_radio *radio = v4l2_ctrl_handler_to_radio(ctrl->handler);
> +
> +     si476x_core_lock(radio->core);
> +
> +     switch (ctrl->id) {
> +     case SI476X_CID_HARMONICS_COUNT:
> +             retval = regmap_update_bits(radio->core->regmap,
> +                                         SI476X_PROP_AUDIO_PWR_LINE_FILTER,
> +                                         SI476X_PROP_PWR_HARMONICS_MASK,
> +                                         ctrl->val);
> +             break;
> +     case V4L2_CID_POWER_LINE_FREQUENCY:
> +             switch (ctrl->val) {
> +             case V4L2_CID_POWER_LINE_FREQUENCY_DISABLED:
> +                     retval = regmap_update_bits(radio->core->regmap,
> +                                                 
> SI476X_PROP_AUDIO_PWR_LINE_FILTER,
> +                                                 SI476X_PROP_PWR_ENABLE_MASK,
> +                                                 0);
> +                     break;
> +             case V4L2_CID_POWER_LINE_FREQUENCY_50HZ:
> +                     retval = regmap_update_bits(radio->core->regmap,
> +                                                 
> SI476X_PROP_AUDIO_PWR_LINE_FILTER,
> +                                                 SI476X_PROP_PWR_GRID_MASK,
> +                                                 SI476X_PROP_PWR_GRID_50HZ);
> +                     break;
> +             case V4L2_CID_POWER_LINE_FREQUENCY_60HZ:
> +                     retval = regmap_update_bits(radio->core->regmap,
> +                                                 
> SI476X_PROP_AUDIO_PWR_LINE_FILTER,
> +                                                 SI476X_PROP_PWR_GRID_MASK,
> +                                                 SI476X_PROP_PWR_GRID_60HZ);
> +                     break;
> +             default:
> +                     retval = -EINVAL;
> +                     break;
> +             }
> +             break;
> +     case SI476X_CID_RSSI_THRESHOLD:
> +             retval = regmap_write(radio->core->regmap,
> +                                   SI476X_PROP_VALID_RSSI_THRESHOLD,
> +                                   ctrl->val);
> +             break;
> +     case SI476X_CID_SNR_THRESHOLD:
> +             retval = regmap_write(radio->core->regmap,
> +                                   SI476X_PROP_VALID_SNR_THRESHOLD,
> +                                   ctrl->val);
> +             break;
> +     case SI476X_CID_MAX_TUNE_ERROR:
> +             retval = regmap_write(radio->core->regmap,
> +                                   SI476X_PROP_VALID_MAX_TUNE_ERROR,
> +                                   ctrl->val);
> +             break;
> +     case SI476X_CID_RDS_RECEPTION:
> +             /*
> +              * It looks like RDS related properties are
> +              * inaccesable when tuner is in AM mode, so cache the
> +              * changes
> +              */
> +             if(si476x_core_is_in_am_receiver_mode(radio->core))
> +                     regcache_cache_only(radio->core->regmap, true);
> +
> +             if (ctrl->val) {
> +                     retval = regmap_write(radio->core->regmap,
> +                                           
> SI476X_PROP_FM_RDS_INTERRUPT_FIFO_COUNT,
> +                                           radio->core->rds_fifo_depth);
> +                     if (retval < 0)
> +                             break;
> +
> +                     if (radio->core->client->irq) {
> +                             retval = regmap_write(radio->core->regmap,
> +                                                   
> SI476X_PROP_FM_RDS_INTERRUPT_SOURCE,
> +                                                   SI476X_RDSRECV);
> +                             if (retval < 0)
> +                                     break;
> +                     }
> +
> +                     /* Drain RDS FIFO before enabling RDS processing */
> +                     retval = si476x_core_cmd_fm_rds_status(radio->core, 
> false,
> +                                                            true, true, 
> NULL);
> +                     if (retval < 0)
> +                             break;
> +
> +                     retval = regmap_update_bits(radio->core->regmap,
> +                                                 SI476X_PROP_FM_RDS_CONFIG,
> +                                                 SI476X_PROP_RDSEN_MASK,
> +                                                 SI476X_PROP_RDSEN);
> +             } else {
> +                     retval = regmap_update_bits(radio->core->regmap,
> +                                                 SI476X_PROP_FM_RDS_CONFIG,
> +                                                 SI476X_PROP_RDSEN_MASK,
> +                                                 !SI476X_PROP_RDSEN);
> +             }
> +
> +             if(si476x_core_is_in_am_receiver_mode(radio->core))
> +                     regcache_cache_only(radio->core->regmap, false);
> +             break;
> +     case SI476X_CID_DEEMPHASIS:
> +             retval = regmap_write(radio->core->regmap,
> +                                   SI476X_PROP_AUDIO_DEEMPHASIS,
> +                                   ctrl->val);
> +             break;
> +
> +     case SI476X_CID_DIVERSITY_MODE:
> +             mode = si476x_phase_diversity_idx_to_mode(ctrl->val);
> +
> +             if (mode == radio->core->diversity_mode) {
> +                     retval = 0;
> +                     break;
> +             }
> +
> +             if(si476x_core_is_in_am_receiver_mode(radio->core)) {
> +                     /*
> +                      * Diversity cannot be configured while tuner
> +                      * is in AM mode so save tha changes and carry on.
> +                      */
> +                     radio->core->diversity_mode = mode;
> +                     retval = 0;
> +             } else {
> +                     retval = radio->ops->phase_diversity(radio->core, mode);
> +                     if (!retval)
> +                             radio->core->diversity_mode = mode;
> +             }
> +             break;
> +
> +     default:
> +             retval = -EINVAL;
> +             break;
> +     }
> +
> +     si476x_core_unlock(radio->core);
> +
> +     return retval;
> +}
> +
> +static int si476x_radio_g_chip_ident(struct file *file, void *fh,
> +                                  struct v4l2_dbg_chip_ident *chip)
> +{
> +     if (chip->match.type == V4L2_CHIP_MATCH_HOST &&
> +         v4l2_chip_match_host(&chip->match))
> +             return 0;
> +     return -EINVAL;
> +}
> +
> +
> +#ifdef CONFIG_VIDEO_ADV_DEBUG
> +static int si476x_radio_g_register(struct file *file, void *fh,
> +                                struct v4l2_dbg_register *reg)
> +{
> +     int err;
> +     unsigned int value;
> +     struct si476x_radio *radio = video_drvdata(file);
> +
> +     si476x_core_lock(radio->core);
> +     reg->size = 2;
> +     err = regmap_read(radio->core->regmap,
> +                       (unsigned int)reg->reg, &value);
> +     reg->val = value;
> +     si476x_core_unlock(radio->core);
> +
> +     return err;
> +}
> +static int si476x_radio_s_register(struct file *file, void *fh,
> +                                struct v4l2_dbg_register *reg)
> +{
> +
> +     int err;
> +     struct si476x_radio *radio = video_drvdata(file);
> +
> +     si476x_core_lock(radio->core);
> +     err = regmap_write(radio->core->regmap,
> +                        (unsigned int)reg->reg,
> +                        (unsigned int)reg->val);
> +     si476x_core_unlock(radio->core);
> +
> +     return err;
> +}
> +#endif
> +
> +static int si476x_radio_fops_open(struct file *file)
> +{
> +     struct si476x_radio *radio = video_drvdata(file);
> +     int err;
> +
> +     err = v4l2_fh_open(file);
> +     if (err)
> +             return err;
> +
> +     if (v4l2_fh_is_singular_file(file)) {
> +             si476x_core_lock(radio->core);
> +             err = si476x_core_set_power_state(radio->core,
> +                                               SI476X_POWER_UP_FULL);
> +             if (err < 0)
> +                     goto done;
> +
> +             err = si476x_radio_do_post_powerup_init(radio,
> +                                                     
> radio->core->power_up_parameters.func);
> +             if (err < 0)
> +                     goto power_down;
> +
> +             err = si476x_radio_pretune(radio,
> +                                        
> radio->core->power_up_parameters.func);
> +             if (err < 0)
> +                     goto power_down;
> +
> +             si476x_core_unlock(radio->core);
> +             /* Must be done after si476x_core_unlock to prevent a deadlock 
> */
> +             v4l2_ctrl_handler_setup(&radio->ctrl_handler);
> +     }
> +
> +     return err;
> +
> +power_down:
> +     si476x_core_set_power_state(radio->core,
> +                                 SI476X_POWER_DOWN);
> +done:
> +     si476x_core_unlock(radio->core);
> +     v4l2_fh_release(file);
> +
> +     return err;
> +}
> +
> +static int si476x_radio_fops_release(struct file *file)
> +{
> +     int err;
> +     struct si476x_radio *radio = video_drvdata(file);
> +
> +     if (v4l2_fh_is_singular_file(file) &&
> +         atomic_read(&radio->core->is_alive))
> +             si476x_core_set_power_state(radio->core,
> +                                         SI476X_POWER_DOWN);
> +
> +     err = v4l2_fh_release(file);
> +
> +     return err;
> +}
> +
> +static ssize_t si476x_radio_fops_read(struct file *file, char __user *buf,
> +                                   size_t count, loff_t *ppos)
> +{
> +     ssize_t      rval;
> +     size_t       fifo_len;
> +     unsigned int copied;
> +
> +     struct si476x_radio *radio = video_drvdata(file);
> +
> +     /* block if no new data available */
> +     if (kfifo_is_empty(&radio->core->rds_fifo)) {
> +             if (file->f_flags & O_NONBLOCK)
> +                     return -EWOULDBLOCK;
> +
> +             rval = wait_event_interruptible(radio->core->rds_read_queue,
> +                                             
> (!kfifo_is_empty(&radio->core->rds_fifo) ||
> +                                              
> !atomic_read(&radio->core->is_alive)));
> +             if (rval < 0)
> +                     return -EINTR;
> +
> +             if (!atomic_read(&radio->core->is_alive))
> +                     return -ENODEV;
> +     }
> +
> +     fifo_len = kfifo_len(&radio->core->rds_fifo);
> +
> +     if (kfifo_to_user(&radio->core->rds_fifo, buf,
> +                       min(fifo_len, count),
> +                       &copied) != 0) {
> +             dev_warn(&radio->videodev.dev,
> +                      "Error during FIFO to userspace copy\n");
> +             rval = -EIO;
> +     } else {
> +             rval = (ssize_t)copied;
> +     }
> +
> +     return rval;
> +}
> +
> +static unsigned int si476x_radio_fops_poll(struct file *file,
> +                             struct poll_table_struct *pts)
> +{
> +     struct si476x_radio *radio = video_drvdata(file);
> +     unsigned long req_events = poll_requested_events(pts);
> +     int err = v4l2_ctrl_poll(file, pts);
> +
> +     if (req_events & (POLLIN | POLLRDNORM)) {
> +             if (atomic_read(&radio->core->is_alive))
> +                     poll_wait(file, &radio->core->rds_read_queue, pts);
> +
> +             if (!atomic_read(&radio->core->is_alive))
> +                     err = POLLHUP;
> +
> +             if (!kfifo_is_empty(&radio->core->rds_fifo))
> +                     err = POLLIN | POLLRDNORM;
> +     }
> +
> +     return err;
> +}
> +
> +static const struct v4l2_file_operations si476x_fops = {
> +     .owner                  = THIS_MODULE,
> +     .read                   = si476x_radio_fops_read,
> +     .poll                   = si476x_radio_fops_poll,
> +     .unlocked_ioctl         = video_ioctl2,
> +     .open                   = si476x_radio_fops_open,
> +     .release                = si476x_radio_fops_release,
> +};
> +
> +
> +static const struct v4l2_ioctl_ops si4761_ioctl_ops = {
> +     .vidioc_querycap                = si476x_radio_querycap,
> +     .vidioc_g_tuner                 = si476x_radio_g_tuner,
> +     .vidioc_s_tuner                 = si476x_radio_s_tuner,
> +
> +     .vidioc_g_frequency             = si476x_radio_g_frequency,
> +     .vidioc_s_frequency             = si476x_radio_s_frequency,
> +     .vidioc_s_hw_freq_seek          = si476x_radio_s_hw_freq_seek,
> +     .vidioc_enum_freq_bands         = si476x_radio_enum_freq_bands,
> +
> +     .vidioc_subscribe_event         = v4l2_ctrl_subscribe_event,
> +     .vidioc_unsubscribe_event       = v4l2_event_unsubscribe,
> +
> +     .vidioc_g_chip_ident            = si476x_radio_g_chip_ident,
> +#ifdef CONFIG_VIDEO_ADV_DEBUG
> +     .vidioc_g_register              = si476x_radio_g_register,
> +     .vidioc_s_register              = si476x_radio_s_register,
> +#endif
> +};
> +
> +
> +static const struct video_device si476x_viddev_template = {
> +     .fops                   = &si476x_fops,
> +     .name                   = DRIVER_NAME,
> +     .release                = video_device_release_empty,
> +};
> +
> +
> +
> +static ssize_t si476x_radio_read_acf_blob(struct file *file, char __user 
> *user_buf,
> +                                       size_t count, loff_t *ppos)
> +{
> +     int err;
> +     struct si476x_radio *radio = file->private_data;
> +     struct si476x_acf_status_report report;
> +
> +     si476x_core_lock(radio->core);
> +     if (radio->ops->acf_status)
> +             err = radio->ops->acf_status(radio->core, &report);
> +     else
> +             err = -ENOENT;
> +     si476x_core_unlock(radio->core);
> +
> +     if (err < 0)
> +             return err;
> +
> +     return simple_read_from_buffer(user_buf, count, ppos, &report,
> +                                    sizeof(report));
> +}
> +
> +static const struct file_operations radio_acf_fops = {
> +     .open   = simple_open,
> +     .llseek = default_llseek,
> +     .read   = si476x_radio_read_acf_blob,
> +};
> +
> +static ssize_t si476x_radio_read_rds_blckcnt_blob(struct file *file, char 
> __user *user_buf,
> +                                               size_t count, loff_t *ppos)
> +{
> +     int err;
> +     struct si476x_radio *radio = file->private_data;
> +     struct si476x_rds_blockcount_report report;
> +
> +     si476x_core_lock(radio->core);
> +     if (radio->ops->rds_blckcnt)
> +             err = radio->ops->rds_blckcnt(radio->core, true,
> +                                            &report);
> +     else
> +             err = -ENOENT;
> +     si476x_core_unlock(radio->core);
> +
> +     if (err < 0)
> +             return err;
> +
> +     return simple_read_from_buffer(user_buf, count, ppos, &report,
> +                                    sizeof(report));
> +}
> +
> +static const struct file_operations radio_rds_blckcnt_fops = {
> +     .open   = simple_open,
> +     .llseek = default_llseek,
> +     .read   = si476x_radio_read_rds_blckcnt_blob,
> +};
> +
> +static ssize_t si476x_radio_read_agc_blob(struct file *file, char __user 
> *user_buf,
> +                                               size_t count, loff_t *ppos)
> +{
> +     int err;
> +     struct si476x_radio *radio = file->private_data;
> +     struct si476x_agc_status_report report;
> +
> +     si476x_core_lock(radio->core);
> +     if (radio->ops->rds_blckcnt)
> +             err = radio->ops->agc_status(radio->core, &report);
> +     else
> +             err = -ENOENT;
> +     si476x_core_unlock(radio->core);
> +
> +     if (err < 0)
> +             return err;
> +
> +     return simple_read_from_buffer(user_buf, count, ppos, &report,
> +                                    sizeof(report));
> +}
> +
> +static const struct file_operations radio_agc_fops = {
> +     .open   = simple_open,
> +     .llseek = default_llseek,
> +     .read   = si476x_radio_read_agc_blob,
> +};
> +
> +static ssize_t si476x_radio_read_rsq_blob(struct file *file, char __user 
> *user_buf,
> +                                       size_t count, loff_t *ppos)
> +{
> +     int err;
> +     struct si476x_radio *radio = file->private_data;
> +     struct si476x_rsq_status_report report;
> +     struct si476x_rsq_status_args args = {
> +             .primary        = false,
> +             .rsqack         = false,
> +             .attune         = false,
> +             .cancel         = false,
> +             .stcack         = false,
> +     };
> +
> +     si476x_core_lock(radio->core);
> +     if (radio->ops->rds_blckcnt)
> +             err = radio->ops->rsq_status(radio->core, &args, &report);
> +     else
> +             err = -ENOENT;
> +     si476x_core_unlock(radio->core);
> +
> +     if (err < 0)
> +             return err;
> +
> +     return simple_read_from_buffer(user_buf, count, ppos, &report,
> +                                    sizeof(report));
> +}
> +
> +static const struct file_operations radio_rsq_fops = {
> +     .open   = simple_open,
> +     .llseek = default_llseek,
> +     .read   = si476x_radio_read_rsq_blob,
> +};
> +
> +static ssize_t si476x_radio_read_rsq_primary_blob(struct file *file,
> +                                               char __user *user_buf,
> +                                               size_t count, loff_t *ppos)
> +{
> +     int err;
> +     struct si476x_radio *radio = file->private_data;
> +     struct si476x_rsq_status_report report;
> +     struct si476x_rsq_status_args args = {
> +             .primary        = true,
> +             .rsqack         = false,
> +             .attune         = false,
> +             .cancel         = false,
> +             .stcack         = false,
> +     };
> +
> +     si476x_core_lock(radio->core);
> +     if (radio->ops->rds_blckcnt)
> +             err = radio->ops->rsq_status(radio->core, &args, &report);
> +     else
> +             err = -ENOENT;
> +     si476x_core_unlock(radio->core);
> +
> +     if (err < 0)
> +             return err;
> +
> +     return simple_read_from_buffer(user_buf, count, ppos, &report,
> +                                    sizeof(report));
> +}
> +
> +static const struct file_operations radio_rsq_primary_fops = {
> +     .open   = simple_open,
> +     .llseek = default_llseek,
> +     .read   = si476x_radio_read_rsq_primary_blob,
> +};
> +
> +
> +static int __devinit si476x_radio_init_debugfs(struct si476x_radio *radio)
> +{
> +     struct dentry   *dentry;
> +     int             ret;
> +
> +     dentry = debugfs_create_dir(dev_name(radio->v4l2dev.dev), NULL);
> +     if (IS_ERR(dentry)) {
> +             ret = PTR_ERR(dentry);
> +             goto exit;
> +     }
> +     radio->debugfs = dentry;
> +
> +     dentry = debugfs_create_file("acf", S_IRUGO,
> +                                  radio->debugfs, radio, &radio_acf_fops);
> +     if (IS_ERR(dentry)) {
> +             ret = PTR_ERR(dentry);
> +             goto cleanup;
> +     }
> +
> +     dentry = debugfs_create_file("rds_blckcnt", S_IRUGO,
> +                                  radio->debugfs, radio, 
> &radio_rds_blckcnt_fops);
> +     if (IS_ERR(dentry)) {
> +             ret = PTR_ERR(dentry);
> +             goto cleanup;
> +     }
> +
> +     dentry = debugfs_create_file("agc", S_IRUGO,
> +                                  radio->debugfs, radio, &radio_agc_fops);
> +     if (IS_ERR(dentry)) {
> +             ret = PTR_ERR(dentry);
> +             goto cleanup;
> +     }
> +
> +     dentry = debugfs_create_file("rsq", S_IRUGO,
> +                                  radio->debugfs, radio, &radio_rsq_fops);
> +     if (IS_ERR(dentry)) {
> +             ret = PTR_ERR(dentry);
> +             goto cleanup;
> +     }
> +
> +     dentry = debugfs_create_file("rsq_primary", S_IRUGO,
> +                                  radio->debugfs, radio, 
> &radio_rsq_primary_fops);

What these files are used for and how to interpret the contents should be
documented somewhere. Usually a document in Documentation/video4linux is a good
place for that.

BTW: have you tested compiling this driver if debugfs is not configured?

> +     if (IS_ERR(dentry)) {
> +             ret = PTR_ERR(dentry);
> +             goto cleanup;
> +     }
> +
> +     return 0;
> +cleanup:
> +     debugfs_remove_recursive(radio->debugfs);
> +exit:
> +     return ret;
> +}
> +
> +
> +static int __devinit si476x_radio_add_new_custom(struct si476x_radio *radio,
> +                                                     enum si476x_ctrl_idx 
> idx)
> +{
> +     int rval;
> +     struct v4l2_ctrl *ctrl;
> +
> +     ctrl = v4l2_ctrl_new_custom(&radio->ctrl_handler,
> +                                 &si476x_ctrls[idx],
> +                                 NULL);
> +     rval = radio->ctrl_handler.error;
> +     if (ctrl == NULL && rval)
> +             dev_err(radio->v4l2dev.dev, "Could not initialize '%s' control 
> %d\n",
> +                     si476x_ctrls[idx].name, rval);
> +
> +     return rval;
> +}
> +
> +static int __devinit si476x_radio_probe(struct platform_device *pdev)
> +{
> +     int rval;
> +     struct si476x_radio *radio;
> +
> +     static atomic_t instance = ATOMIC_INIT(0);
> +
> +     radio = devm_kzalloc(&pdev->dev, sizeof(*radio), GFP_KERNEL);
> +     if (!radio)
> +             return -ENOMEM;
> +
> +     radio->core = i2c_mfd_cell_to_core(&pdev->dev);
> +
> +     v4l2_device_set_name(&radio->v4l2dev, DRIVER_NAME, &instance);
> +
> +     rval = v4l2_device_register(&pdev->dev, &radio->v4l2dev);
> +     if (rval) {
> +             dev_err(&pdev->dev, "Cannot register v4l2_device.\n");
> +             return rval;
> +     }
> +
> +     memcpy(&radio->videodev, &si476x_viddev_template,
> +            sizeof(struct video_device));
> +
> +     radio->videodev.v4l2_dev  = &radio->v4l2dev;
> +     radio->videodev.ioctl_ops = &si4761_ioctl_ops;
> +
> +     video_set_drvdata(&radio->videodev, radio);
> +     platform_set_drvdata(pdev, radio);
> +
> +     set_bit(V4L2_FL_USE_FH_PRIO, &radio->videodev.flags);
> +
> +     radio->v4l2dev.ctrl_handler = &radio->ctrl_handler;
> +     v4l2_ctrl_handler_init(&radio->ctrl_handler, 1 + 
> ARRAY_SIZE(si476x_ctrls));
> +
> +     if (si476x_core_has_am(radio->core)) {
> +             struct v4l2_ctrl *ctrl;
> +
> +             ctrl = v4l2_ctrl_new_std_menu(&radio->ctrl_handler,
> +                                           &si476x_ctrl_ops,
> +                                           V4L2_CID_POWER_LINE_FREQUENCY,
> +                                           
> V4L2_CID_POWER_LINE_FREQUENCY_60HZ, 0, 0);
> +             rval = radio->ctrl_handler.error;
> +             if (ctrl == NULL && rval) {
> +                     dev_err(&pdev->dev, "Could not initialize 
> V4L2_CID_POWER_LINE_FREQUENCY control %d\n",
> +                             rval);
> +                     goto exit;
> +             }
> +
> +             rval = si476x_radio_add_new_custom(radio, 
> SI476X_IDX_HARMONICS_COUNT);
> +             if (rval < 0)
> +                     goto exit;
> +     }
> +
> +     rval = si476x_radio_add_new_custom(radio, SI476X_IDX_RSSI_THRESHOLD);
> +     if (rval < 0)
> +             goto exit;
> +
> +     rval = si476x_radio_add_new_custom(radio, SI476X_IDX_SNR_THRESHOLD);
> +     if (rval < 0)
> +             goto exit;
> +
> +     rval = si476x_radio_add_new_custom(radio, SI476X_IDX_MAX_TUNE_ERROR);
> +     if (rval < 0)
> +             goto exit;
> +
> +     rval = si476x_radio_add_new_custom(radio, SI476X_IDX_DEEMPHASIS);
> +     if (rval < 0)
> +             goto exit;
> +
> +     rval = si476x_radio_add_new_custom(radio, SI476X_IDX_RDS_RECEPTION);
> +     if (rval < 0)
> +             goto exit;
> +
> +     if (si476x_core_has_diversity(radio->core)) {
> +             si476x_ctrls[SI476X_IDX_DIVERSITY_MODE].def =
> +                     
> si476x_phase_diversity_mode_to_idx(radio->core->diversity_mode);
> +             si476x_radio_add_new_custom(radio, SI476X_IDX_DIVERSITY_MODE);
> +             if (rval < 0)
> +                     goto exit;
> +
> +             si476x_radio_add_new_custom(radio, SI476X_IDX_INTERCHIP_LINK);
> +             if (rval < 0)
> +                     goto exit;
> +     }
> +
> +     /* register video device */
> +     rval = video_register_device(&radio->videodev, VFL_TYPE_RADIO, -1);
> +     if (rval < 0) {
> +             dev_err(&pdev->dev, "Could not register video device\n");
> +             goto exit;
> +     }
> +
> +     rval = si476x_radio_init_debugfs(radio);
> +     if (rval < 0) {
> +             dev_err(&pdev->dev, "Could not creat debugfs interface\n");
> +             goto exit;
> +     }
> +
> +     return 0;
> +exit:
> +     v4l2_ctrl_handler_free(radio->videodev.ctrl_handler);
> +     return rval;
> +}
> +
> +static int si476x_radio_remove(struct platform_device *pdev)
> +{
> +     struct si476x_radio *radio = platform_get_drvdata(pdev);
> +
> +     v4l2_ctrl_handler_free(radio->videodev.ctrl_handler);
> +     video_unregister_device(&radio->videodev);
> +     v4l2_device_unregister(&radio->v4l2dev);
> +     debugfs_remove_recursive(radio->debugfs);
> +
> +     return 0;
> +}
> +
> +MODULE_ALIAS("platform:si476x-radio");
> +
> +static struct platform_driver si476x_radio_driver = {
> +     .probe          = si476x_radio_probe,
> +     .remove         = __devexit_p(si476x_radio_remove),
> +     .driver         = {
> +             .name   = DRIVER_NAME,
> +             .owner  = THIS_MODULE,
> +     },
> +};
> +
> +static int __init si476x_module_init(void)
> +{
> +     return platform_driver_register(&si476x_radio_driver);
> +}
> +module_init(si476x_module_init);
> +
> +static void __exit si476x_module_exit(void)
> +{
> +     platform_driver_unregister(&si476x_radio_driver);
> +}
> +module_exit(si476x_module_exit);
> +
> +MODULE_AUTHOR("Andrey Smirnov <andrey.smir...@convergeddevices.net>");
> +MODULE_DESCRIPTION("Driver for Si4761/64/68 AM/FM Radio MFD Cell");
> +MODULE_LICENSE("GPL");
> 

Regards,

        Hans
--
To unsubscribe from this list: send the line "unsubscribe linux-media" in
the body of a message to majord...@vger.kernel.org
More majordomo info at  http://vger.kernel.org/majordomo-info.html

Reply via email to