Sakari, thanks for your review.
On 11/6/20 7:50 PM, Sakari Ailus wrote:
> 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.
The 'ready' field was also used to mark the OTP data loading during streaming, in patch 2/2.
Your comments inspired me, I think I could move the ready checking into OTP data read in v2.
>
>> + 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);
>>
>
--
Best regards,
Bingbu Cao
