Hi Krysztof, On Mon, Oct 19, 2020 at 07:26:17PM +0200, Krzysztof Kozlowski wrote: > The IMX258 sensor driver checked in device properties for a > clock-frequency property which actually does not mean that the clock is > really running such frequency or is it even enabled. > > Get the provided clock and check it frequency. If none is provided, > fall back to old property. > > Enable the clock when accessing the IMX258 registers and when streaming > starts with runtime PM. > > Signed-off-by: Krzysztof Kozlowski <k...@kernel.org> > > --- > > Changes since v4: > 1. Add missing imx258_power_off. > > Changes since v3: > 1. None > > Changes since v2: > 1. Do not try to set drvdata, wrap lines. > 2. Use dev_dbg. > > Changes since v1: > 1. Use runtime PM for clock toggling > --- > drivers/media/i2c/imx258.c | 73 +++++++++++++++++++++++++++++++++----- > 1 file changed, 64 insertions(+), 9 deletions(-) > > diff --git a/drivers/media/i2c/imx258.c b/drivers/media/i2c/imx258.c > index ae183b0dbba9..038115471f17 100644 > --- a/drivers/media/i2c/imx258.c > +++ b/drivers/media/i2c/imx258.c > @@ -2,6 +2,7 @@ > // Copyright (C) 2018 Intel Corporation > > #include <linux/acpi.h> > +#include <linux/clk.h> > #include <linux/delay.h> > #include <linux/i2c.h> > #include <linux/module.h> > @@ -68,6 +69,9 @@ > #define REG_CONFIG_MIRROR_FLIP 0x03 > #define REG_CONFIG_FLIP_TEST_PATTERN 0x02 > > +/* Input clock frequency in Hz */ > +#define IMX258_INPUT_CLOCK_FREQ 19200000 > + > struct imx258_reg { > u16 address; > u8 val; > @@ -610,6 +614,8 @@ struct imx258 { > > /* Streaming on/off */ > bool streaming; > + > + struct clk *clk; > }; > > static inline struct imx258 *to_imx258(struct v4l2_subdev *_sd) > @@ -972,6 +978,29 @@ static int imx258_stop_streaming(struct imx258 *imx258) > return 0; > } > > +static int imx258_power_on(struct device *dev) > +{ > + struct v4l2_subdev *sd = dev_get_drvdata(dev); > + struct imx258 *imx258 = to_imx258(sd); > + int ret; > + > + ret = clk_prepare_enable(imx258->clk); > + if (ret) > + dev_err(dev, "failed to enable clock\n"); > + > + return ret; > +} > + > +static int imx258_power_off(struct device *dev) > +{ > + struct v4l2_subdev *sd = dev_get_drvdata(dev); > + struct imx258 *imx258 = to_imx258(sd); > + > + clk_disable_unprepare(imx258->clk); > + > + return 0; > +} > + > static int imx258_set_stream(struct v4l2_subdev *sd, int enable) > { > struct imx258 *imx258 = to_imx258(sd); > @@ -1199,9 +1228,28 @@ static int imx258_probe(struct i2c_client *client) > int ret; > u32 val = 0; > > - device_property_read_u32(&client->dev, "clock-frequency", &val); > - if (val != 19200000) > - return -EINVAL; > + imx258 = devm_kzalloc(&client->dev, sizeof(*imx258), GFP_KERNEL); > + if (!imx258) > + return -ENOMEM; > + > + imx258->clk = devm_clk_get_optional(&client->dev, NULL); > + if (!imx258->clk) { > + dev_dbg(&client->dev, > + "no clock provided, using clock-frequency property\n"); > + > + device_property_read_u32(&client->dev, "clock-frequency", &val); > + if (val != IMX258_INPUT_CLOCK_FREQ) > + return -EINVAL; > + } else if (IS_ERR(imx258->clk)) { > + return dev_err_probe(&client->dev, PTR_ERR(imx258->clk), > + "error getting clock\n"); > + } else { > + if (clk_get_rate(imx258->clk) != IMX258_INPUT_CLOCK_FREQ) {
Please move the check outside the conditional block. May be a separate patch if you like. > + dev_err(&client->dev, > + "input clock frequency not supported\n"); > + return -EINVAL; > + } > + } > > /* > * Check that the device is mounted upside down. The driver only > @@ -1211,24 +1259,25 @@ static int imx258_probe(struct i2c_client *client) > if (ret || val != 180) > return -EINVAL; > > - imx258 = devm_kzalloc(&client->dev, sizeof(*imx258), GFP_KERNEL); > - if (!imx258) > - return -ENOMEM; > - > /* Initialize subdev */ > v4l2_i2c_subdev_init(&imx258->sd, client, &imx258_subdev_ops); > > + /* Will be powered off via pm_runtime_idle */ > + ret = imx258_power_on(&client->dev); > + if (ret) > + return ret; > + > /* Check module identity */ > ret = imx258_identify_module(imx258); > if (ret) > - return ret; > + goto error_identify; > > /* Set default mode to max resolution */ > imx258->cur_mode = &supported_modes[0]; > > ret = imx258_init_controls(imx258); > if (ret) > - return ret; > + goto error_identify; > > /* Initialize subdev */ > imx258->sd.internal_ops = &imx258_internal_ops; > @@ -1258,6 +1307,9 @@ static int imx258_probe(struct i2c_client *client) > error_handler_free: > imx258_free_controls(imx258); > > +error_identify: > + imx258_power_off(&client->dev); > + > return ret; > } > > @@ -1271,6 +1323,8 @@ static int imx258_remove(struct i2c_client *client) > imx258_free_controls(imx258); > > pm_runtime_disable(&client->dev); > + if (!pm_runtime_status_suspended(&client->dev)) > + imx258_power_off(&client->dev); > pm_runtime_set_suspended(&client->dev); > > return 0; > @@ -1278,6 +1332,7 @@ static int imx258_remove(struct i2c_client *client) > > static const struct dev_pm_ops imx258_pm_ops = { > SET_SYSTEM_SLEEP_PM_OPS(imx258_suspend, imx258_resume) > + SET_RUNTIME_PM_OPS(imx258_power_off, imx258_power_on, NULL) > }; > > #ifdef CONFIG_ACPI -- Kind regards, Sakari Ailus