Hi Bingbu,
Thanks for the patch.
On Fri, Nov 06, 2020 at 02:40:43PM +0800, Bingbu Cao wrote:
> OTP data access of ov2740 in probe need power up, it may cause
> the camera flash LED blink during probe if the LED use same power
> rail with camera, this patch move the OTP data access out of
> probe, it will only occur on demand from user by nvmem sysfs.
>
> Signed-off-by: Bingbu Cao <bingbu.cao@xxxxxxxxx>
> Signed-off-by: Qingwu Zhang <qingwu.zhang@xxxxxxxxx>
> ---
> drivers/media/i2c/ov2740.c | 63 +++++++++++++++++++++++++++++++++++-----------
> 1 file changed, 48 insertions(+), 15 deletions(-)
>
> diff --git a/drivers/media/i2c/ov2740.c b/drivers/media/i2c/ov2740.c
> index 64ecb6917dd3..716c26c13c97 100644
> --- a/drivers/media/i2c/ov2740.c
> +++ b/drivers/media/i2c/ov2740.c
> @@ -71,9 +71,11 @@
> #define OV2740_REG_OTP_CUSTOMER 0x7010
>
> struct nvm_data {
> - char *nvm_buffer;
> + struct i2c_client *client;
> struct nvmem_device *nvmem;
> struct regmap *regmap;
> + char *nvm_buffer;
> + bool ready;
> };
>
> enum {
> @@ -335,6 +337,9 @@ struct ov2740 {
>
> /* Streaming on/off */
> bool streaming;
> +
> + /* NVM data inforamtion */
> + struct nvm_data *nvm;
> };
>
> static inline struct ov2740 *to_ov2740(struct v4l2_subdev *subdev)
> @@ -930,8 +935,9 @@ static int ov2740_remove(struct i2c_client *client)
> return 0;
> }
>
> -static int ov2740_load_otp_data(struct i2c_client *client, struct nvm_data *nvm)
> +static int ov2740_load_otp_data(struct nvm_data *nvm)
> {
> + struct i2c_client *client = nvm->client;
> struct ov2740 *ov2740 = to_ov2740(i2c_get_clientdata(client));
> u32 isp_ctrl00 = 0;
> u32 isp_ctrl01 = 0;
> @@ -967,7 +973,7 @@ static int ov2740_load_otp_data(struct i2c_client *client, struct nvm_data *nvm)
> ret = ov2740_write_reg(ov2740, OV2740_REG_MODE_SELECT, 1,
> OV2740_MODE_STREAMING);
> if (ret) {
> - dev_err(&client->dev, "failed to start streaming\n");
> + dev_err(&client->dev, "failed to set streaming mode\n");
> goto exit;
> }
>
> @@ -997,20 +1003,48 @@ static int ov2740_nvmem_read(void *priv, unsigned int off, void *val,
> size_t count)
> {
> struct nvm_data *nvm = priv;
> + struct v4l2_subdev *sd = i2c_get_clientdata(nvm->client);
> + struct device *dev = &nvm->client->dev;
> + struct ov2740 *ov2740 = to_ov2740(sd);
> + int ret = 0;
> +
> + mutex_lock(&ov2740->mutex);
>
> - memcpy(val, nvm->nvm_buffer + off, count);
> + if (!nvm->ready) {
> + if (ov2740->streaming) {
> + ret = -EBUSY;
> + goto exit;
> + }
>
> - return 0;
If you also moved memory allocation here, you could omit the ready field. I
think it'd be cleaner that way as well.
> + ret = pm_runtime_get_sync(dev);
> + if (ret < 0) {
> + pm_runtime_put_noidle(dev);
> + goto exit;
> + }
> + ret = ov2740_load_otp_data(nvm);
> + if (!ret)
> + nvm->ready = true;
> + pm_runtime_put(dev);
> + }
> +
> +exit:
> + mutex_unlock(&ov2740->mutex);
> +
> + if (!ret)
> + memcpy(val, nvm->nvm_buffer + off, count);
> +
> + return ret;
> }
>
> -static int ov2740_register_nvmem(struct i2c_client *client)
> +static int ov2740_register_nvmem(struct i2c_client *client,
> + struct ov2740 *ov2740)
> {
> struct nvm_data *nvm;
> struct regmap_config regmap_config = { };
> struct nvmem_config nvmem_config = { };
> struct regmap *regmap;
> struct device *dev = &client->dev;
> - int ret = 0;
> + int ret;
>
> nvm = devm_kzalloc(dev, sizeof(*nvm), GFP_KERNEL);
> if (!nvm)
> @@ -1028,12 +1062,7 @@ static int ov2740_register_nvmem(struct i2c_client *client)
> return PTR_ERR(regmap);
>
> nvm->regmap = regmap;
> -
> - ret = ov2740_load_otp_data(client, nvm);
> - if (ret) {
> - dev_err(dev, "failed to load OTP data, ret %d\n", ret);
> - return ret;
> - }
> + nvm->client = client;
>
> nvmem_config.name = dev_name(dev);
> nvmem_config.dev = dev;
> @@ -1051,7 +1080,11 @@ static int ov2740_register_nvmem(struct i2c_client *client)
>
> nvm->nvmem = devm_nvmem_register(dev, &nvmem_config);
>
> - return PTR_ERR_OR_ZERO(nvm->nvmem);
> + ret = PTR_ERR_OR_ZERO(nvm->nvmem);
> + if (!ret)
> + ov2740->nvm = nvm;
> +
> + return ret;
> }
>
> static int ov2740_probe(struct i2c_client *client)
> @@ -1103,7 +1136,7 @@ static int ov2740_probe(struct i2c_client *client)
> goto probe_error_media_entity_cleanup;
> }
>
> - ret = ov2740_register_nvmem(client);
> + ret = ov2740_register_nvmem(client, ov2740);
> if (ret)
> dev_warn(&client->dev, "register nvmem failed, ret %d\n", ret);
>
--
Regards,
Sakari Ailus
