On Thu, Jan 24, 2019 at 11:37:33PM +0530, Jagan Teki wrote:
> CSI block in Allwinner A64 has similar features as like in H3,
> but the default CSI_SCLK rate cannot work properly to drive the
> connected sensor interface.
> 
> The tested mod cock rate is 300 MHz and BSP vfe media driver is also
> using the same rate. Unfortunately there is no valid information about
> clock rate in manual or any other sources except the BSP driver. so more
> faith on BSP code, because same has tested in mainline.
> 
> So, add support for A64 CSI block by setting updated mod clock rate.
> 
> Signed-off-by: Jagan Teki <jagan@amarulasolutions.com>
> ---
>  drivers/media/platform/sunxi/sun6i-csi/sun6i_csi.c | 13 ++++++++++++-
>  1 file changed, 12 insertions(+), 1 deletion(-)
> 
> diff --git a/drivers/media/platform/sunxi/sun6i-csi/sun6i_csi.c b/drivers/media/platform/sunxi/sun6i-csi/sun6i_csi.c
> index ee882b66a5ea..cd2d33242c17 100644
> --- a/drivers/media/platform/sunxi/sun6i-csi/sun6i_csi.c
> +++ b/drivers/media/platform/sunxi/sun6i-csi/sun6i_csi.c
> @@ -15,6 +15,7 @@
>  #include <linux/ioctl.h>
>  #include <linux/module.h>
>  #include <linux/of.h>
> +#include <linux/of_device.h>
>  #include <linux/platform_device.h>
>  #include <linux/pm_runtime.h>
>  #include <linux/regmap.h>
> @@ -154,6 +155,7 @@ bool sun6i_csi_is_format_supported(struct sun6i_csi *csi,
>  int sun6i_csi_set_power(struct sun6i_csi *csi, bool enable)
>  {
>  	struct sun6i_csi_dev *sdev = sun6i_csi_to_dev(csi);
> +	struct device *dev = sdev->dev;
>  	struct regmap *regmap = sdev->regmap;
>  	int ret;
>  
> @@ -161,15 +163,20 @@ int sun6i_csi_set_power(struct sun6i_csi *csi, bool enable)
>  		regmap_update_bits(regmap, CSI_EN_REG, CSI_EN_CSI_EN, 0);
>  
>  		clk_disable_unprepare(sdev->clk_ram);
> +		if (of_device_is_compatible(dev->of_node, "allwinner,sun50i-a64-csi"))
> +			clk_rate_exclusive_put(sdev->clk_mod);
>  		clk_disable_unprepare(sdev->clk_mod);
>  		reset_control_assert(sdev->rstc_bus);
>  		return 0;
>  	}
>  
> +	if (of_device_is_compatible(dev->of_node, "allwinner,sun50i-a64-csi"))
> +		clk_set_rate_exclusive(sdev->clk_mod, 300000000);
> +
>  	ret = clk_prepare_enable(sdev->clk_mod);
>  	if (ret) {
>  		dev_err(sdev->dev, "Enable csi clk err %d\n", ret);
> -		return ret;
> +		goto clk_mod_put;
>  	}
>  
>  	ret = clk_prepare_enable(sdev->clk_ram);
> @@ -192,6 +199,9 @@ int sun6i_csi_set_power(struct sun6i_csi *csi, bool enable)
>  	clk_disable_unprepare(sdev->clk_ram);
>  clk_mod_disable:
>  	clk_disable_unprepare(sdev->clk_mod);
> +clk_mod_put:
> +	if (of_device_is_compatible(dev->of_node, "allwinner,sun50i-a64-csi"))
> +		clk_rate_exclusive_put(sdev->clk_mod);
>  	return ret;

The sequence in the error path and in the disable path aren't the same, why?

Maxime

-- 
Maxime Ripard, Bootlin
Embedded Linux and Kernel engineering
https://bootlin.com