[PATCH v3 09/10] media: ar0521: Rework startup sequence

Jacopo Mondi
2022-11-04T14:28:20Z

The ar0521_write_mode() function explicitly programs the exposure time
register and the test pattern register, which are now setup by the call
to __v4l2_ctrl_handler_setup() in ar0521_set_stream().

Removing those register writes from ar0521_write_mode() reduces the
function to two operations: geometry configuration and pll
configuration.

Move geomerty configuration in the ar0521_set_stream() caller and rename
ar0521_write_mode() to ar0521_pll_config().

Signed-off-by: Jacopo Mondi <jacopo@jmondi.org>
Reviewed-by: Dave Stevenson <dave.stevenson@raspberrypi.com>
---
drivers/media/i2c/ar0521.c | 50 ++++++++++++--------------------------
1 file changed, 16 insertions(+), 34 deletions(-)

diff --git a/drivers/media/i2c/ar0521.c b/drivers/media/i2c/ar0521.c
index 323f583e2029..91fa4cba12f6 100644
--- a/drivers/media/i2c/ar0521.c
+++ b/drivers/media/i2c/ar0521.c
@@ -278,7 +278,7 @@ static u32 calc_pll(struct ar0521_dev *sensor, u32 freq, u16 *pre_ptr, u16 *mult
return pll;
}

-static void ar0521_calc_mode(struct ar0521_dev *sensor)
+static void ar0521_calc_pll(struct ar0521_dev *sensor)
{
unsigned int pixel_clock;
u16 pre, mult;
@@ -342,7 +342,7 @@ static void ar0521_calc_mode(struct ar0521_dev *sensor)
sensor->pll.mult = sensor->pll.mult2 = mult;
}

-static int ar0521_write_mode(struct ar0521_dev *sensor)
+static int ar0521_pll_config(struct ar0521_dev *sensor)
{
__be16 pll_regs[] = {
be(AR0521_REG_VT_PIX_CLK_DIV),
@@ -353,36 +353,9 @@ static int ar0521_write_mode(struct ar0521_dev *sensor)
/* 0x308 */ be(sensor->pll.vt_pix * 2), /* op_pix_clk_div = 2 * vt_pix_clk_div */
/* 0x30A */ be(1) /* op_sys_clk_div */
};
- int ret;
-
- /* Stop streaming for just a moment */
- ret = ar0521_write_reg(sensor, AR0521_REG_RESET,
- AR0521_REG_RESET_DEFAULTS);
- if (ret)
- return ret;
-
- ret = ar0521_set_geometry(sensor);
- if (ret)
- return ret;
-
- ret = ar0521_write_regs(sensor, pll_regs, ARRAY_SIZE(pll_regs));
- if (ret)
- return ret;
-
- ret = ar0521_write_reg(sensor, AR0521_REG_COARSE_INTEGRATION_TIME,
- sensor->ctrls.exposure->val);
- if (ret)
- return ret;
-
- ret = ar0521_write_reg(sensor, AR0521_REG_RESET,
- AR0521_REG_RESET_DEFAULTS |
- AR0521_REG_RESET_STREAM);
- if (ret)
- return ret;

- ret = ar0521_write_reg(sensor, AR0521_REG_TEST_PATTERN_MODE,
- sensor->ctrls.test_pattern->val);
- return ret;
+ ar0521_calc_pll(sensor);
+ return ar0521_write_regs(sensor, pll_regs, ARRAY_SIZE(pll_regs));
}

static int ar0521_set_stream(struct ar0521_dev *sensor, bool on)
@@ -394,8 +367,17 @@ static int ar0521_set_stream(struct ar0521_dev *sensor, bool on)
if (ret < 0)
return ret;

- ar0521_calc_mode(sensor);
- ret = ar0521_write_mode(sensor);
+ /* Stop streaming for just a moment */
+ ret = ar0521_write_reg(sensor, AR0521_REG_RESET,
+ AR0521_REG_RESET_DEFAULTS);
+ if (ret)
+ return ret;
+
+ ret = ar0521_set_geometry(sensor);
+ if (ret)
+ return ret;
+
+ ret = ar0521_pll_config(sensor);
if (ret)
goto err;

@@ -501,7 +483,7 @@ static int ar0521_set_fmt(struct v4l2_subdev *sd,
}

sensor->fmt = format->format;
- ar0521_calc_mode(sensor);
+ ar0521_calc_pll(sensor);

/*
* Update the exposure and blankings limits. Blankings are also reset
--
2.38.1