Rework the MIPI interface startup sequence with the following changes: - Remove MIPI bus initialization from the initial settings blob - At set_power(1) time power up MIPI Tx/Rx and set data and clock lanes in LP11 during 'sleep' and 'idle' with MIPI clock in non-continuous mode. - At s_stream time enable/disable the MIPI interface output. - Restore default settings at set_power(0) time.
Before this commit the sensor MIPI interface was initialized with settings that require a start/stop sequence at power-up time in order to force lanes into LP11 state, as they were initialized in LP00 when in 'sleep mode', which is assumed to be the sensor manual definition for the D-PHY defined stop mode. The stream start/stop was performed by enabling disabling clock gating, and had the side effect to change the lanes sleep mode configuration when stream was stopped. Clock gating/ungating: - ret = ov5640_mod_reg(sensor, OV5640_REG_MIPI_CTRL00, BIT(5), - on ? 0 : BIT(5)); - if (ret) Set lanes in LP11 when in 'sleep mode': - ret = ov5640_write_reg(sensor, OV5640_REG_PAD_OUTPUT00, - on ? 0x00 : 0x70); This commit fixes an issue reported by Jagan Teki on i.MX6 platforms that prevents the host interface from powering up correctly: https://lkml.org/lkml/2018/6/1/38 It also improves MIPI capture operations stability on my testing platform where MIPI capture often failed and returned all-purple frames. fixes: f22996db44e2 ("media: ov5640: add support of DVP parallel interface") Reported-by: Jagan Teki <ja...@amarulasolutions.com> Signed-off-by: Jacopo Mondi <jac...@jmondi.org> --- drivers/media/i2c/ov5640.c | 91 ++++++++++++++++++++++++++++++++++++---------- 1 file changed, 71 insertions(+), 20 deletions(-) diff --git a/drivers/media/i2c/ov5640.c b/drivers/media/i2c/ov5640.c index 1ecbb7a..7bbd1d7 100644 --- a/drivers/media/i2c/ov5640.c +++ b/drivers/media/i2c/ov5640.c @@ -286,10 +286,10 @@ static const struct reg_value ov5640_init_setting_30fps_VGA[] = { {0x3a0d, 0x04, 0, 0}, {0x3a14, 0x03, 0, 0}, {0x3a15, 0xd8, 0, 0}, {0x4001, 0x02, 0, 0}, {0x4004, 0x02, 0, 0}, {0x3000, 0x00, 0, 0}, {0x3002, 0x1c, 0, 0}, {0x3004, 0xff, 0, 0}, {0x3006, 0xc3, 0, 0}, - {0x300e, 0x45, 0, 0}, {0x302e, 0x08, 0, 0}, {0x4300, 0x3f, 0, 0}, + {0x302e, 0x08, 0, 0}, {0x4300, 0x3f, 0, 0}, {0x501f, 0x00, 0, 0}, {0x4713, 0x03, 0, 0}, {0x4407, 0x04, 0, 0}, {0x440e, 0x00, 0, 0}, {0x460b, 0x35, 0, 0}, {0x460c, 0x22, 0, 0}, - {0x4837, 0x0a, 0, 0}, {0x4800, 0x04, 0, 0}, {0x3824, 0x02, 0, 0}, + {0x4837, 0x0a, 0, 0}, {0x3824, 0x02, 0, 0}, {0x5000, 0xa7, 0, 0}, {0x5001, 0xa3, 0, 0}, {0x5180, 0xff, 0, 0}, {0x5181, 0xf2, 0, 0}, {0x5182, 0x00, 0, 0}, {0x5183, 0x14, 0, 0}, {0x5184, 0x25, 0, 0}, {0x5185, 0x24, 0, 0}, {0x5186, 0x09, 0, 0}, @@ -1102,12 +1102,18 @@ static int ov5640_set_stream_mipi(struct ov5640_dev *sensor, bool on) { int ret; - ret = ov5640_mod_reg(sensor, OV5640_REG_MIPI_CTRL00, BIT(5), - on ? 0 : BIT(5)); - if (ret) - return ret; - ret = ov5640_write_reg(sensor, OV5640_REG_PAD_OUTPUT00, - on ? 0x00 : 0x70); + /* + * Enable/disable the MIPI interface + * + * 0x300e = on ? 0x45 : 0x40 + * [7:5] = 001 : 2 data lanes mode + * [4] = 0 : Power up MIPI HS Tx + * [3] = 0 : Power up MIPI LS Rx + * [2] = 1/0 : MIPI interface enable/disable + * [1:0] = 01/00: FIXME: 'debug' + */ + ret = ov5640_write_reg(sensor, OV5640_REG_IO_MIPI_CTRL00, + on ? 0x45 : 0x40); if (ret) return ret; @@ -1786,23 +1792,68 @@ static int ov5640_set_power(struct ov5640_dev *sensor, bool on) if (ret) goto power_off; + /* We're done here for DVP bus, while CSI-2 needs setup. */ + if (sensor->ep.bus_type != V4L2_MBUS_CSI2) + return 0; + + /* + * Power up MIPI HS Tx and LS Rx; 2 data lanes mode + * + * 0x300e = 0x40 + * [7:5] = 001 : 2 data lanes mode + * [4] = 0 : Power up MIPI HS Tx + * [3] = 0 : Power up MIPI LS Rx + * [2] = 0 : MIPI interface disabled + */ + ret = ov5640_write_reg(sensor, + OV5640_REG_IO_MIPI_CTRL00, 0x40); + if (ret) + goto power_off; + + /* + * Gate clock and set LP11 in 'no packets mode' (idle) + * + * 0x4800 = 0x24 + * [5] = 1 : Gate clock when 'no packets' + * [2] = 1 : MIPI bus in LP11 when 'no packets' + */ + ret = ov5640_write_reg(sensor, + OV5640_REG_MIPI_CTRL00, 0x24); + if (ret) + goto power_off; + + /* + * Set data lanes and clock in LP11 when 'sleeping' + * + * 0x3019 = 0x70 + * [6] = 1 : MIPI data lane 2 in LP11 when 'sleeping' + * [5] = 1 : MIPI data lane 1 in LP11 when 'sleeping' + * [4] = 1 : MIPI clock lane in LP11 when 'sleeping' + */ + ret = ov5640_write_reg(sensor, + OV5640_REG_PAD_OUTPUT00, 0x70); + if (ret) + goto power_off; + + /* Give lanes some time to coax into LP11 state. */ + usleep_range(500, 1000); + + } else { if (sensor->ep.bus_type == V4L2_MBUS_CSI2) { - /* - * start streaming briefly followed by stream off in - * order to coax the clock lane into LP-11 state. - */ - ret = ov5640_set_stream_mipi(sensor, true); - if (ret) - goto power_off; - usleep_range(1000, 2000); - ret = ov5640_set_stream_mipi(sensor, false); - if (ret) - goto power_off; + /* Reset MIPI bus settings to their default values. */ + ov5640_write_reg(sensor, + OV5640_REG_IO_MIPI_CTRL00, 0x58); + ov5640_write_reg(sensor, + OV5640_REG_MIPI_CTRL00, 0x04); + ov5640_write_reg(sensor, + OV5640_REG_PAD_OUTPUT00, 0x00); } - return 0; + ov5640_set_power_off(sensor); } + return 0; + power_off: ov5640_set_power_off(sensor); return ret; -- 2.7.4
