Hi, Biju,
On 25.06.2024 18:53, Biju Das wrote:
> Hi Claudiu,
>
>> -----Original Message-----
>> From: Claudiu <claudiu.beznea@xxxxxxxxx>
>> Sent: Tuesday, June 25, 2024 1:14 PM
>> Subject: [PATCH v2 04/12] i2c: riic: Use pm_runtime_resume_and_get()
>>
>> From: Claudiu Beznea <claudiu.beznea.uj@xxxxxxxxxxxxxx>
>>
>> pm_runtime_get_sync() may return with error. In case it returns with error
>> dev->power.usage_count needs to be decremented.
>> dev->pm_runtime_resume_and_get()
>> takes care of this. Thus use it.
>>
>> Signed-off-by: Claudiu Beznea <claudiu.beznea.uj@xxxxxxxxxxxxxx>
>> ---
>>
>> Changes in v2:
>> - delete i2c adapter all the time in remove
>>
>> drivers/i2c/busses/i2c-riic.c | 30 ++++++++++++++++++++++++------
>> 1 file changed, 24 insertions(+), 6 deletions(-)
>>
>> diff --git a/drivers/i2c/busses/i2c-riic.c b/drivers/i2c/busses/i2c-riic.c index
>> 83e4d5e14ab6..002b11b020fa 100644
>> --- a/drivers/i2c/busses/i2c-riic.c
>> +++ b/drivers/i2c/busses/i2c-riic.c
>> @@ -113,6 +113,8 @@ struct riic_irq_desc {
>> char *name;
>> };
>>
>> +static const char * const riic_rpm_err_msg = "Failed to runtime
>> +resume";
>> +
>> static inline void riic_writeb(struct riic_dev *riic, u8 val, u8 offset) {
>> writeb(val, riic->base + riic->info->regs[offset]); @@ -133,10 +135,14 @@ static int
>> riic_xfer(struct i2c_adapter *adap, struct i2c_msg msgs[], int num)
>> struct riic_dev *riic = i2c_get_adapdata(adap);
>> struct device *dev = adap->dev.parent;
>> unsigned long time_left;
>> - int i;
>> + int i, ret;
>> u8 start_bit;
>>
>> - pm_runtime_get_sync(dev);
>> + ret = pm_runtime_resume_and_get(dev);
>> + if (ret) {
>> + dev_err(dev, riic_rpm_err_msg);
>
> As at the moment we don't know how to reproduce this error condition
> Can we use WARN_ON_ONCE() instead to catch detailed error condition here??
[1] states "So, naturally, use of WARN_ON() is also now discouraged much of
the time". I've go with dev_err() or something similar.
Thank you,
Claudiu Beznea
[1] https://lwn.net/Articles/969923/
>
> Cheers,
> Biju
>
>> + return ret;
>> + }
>>
>> if (riic_readb(riic, RIIC_ICCR2) & ICCR2_BBSY) {
>> riic->err = -EBUSY;
>> @@ -301,6 +307,7 @@ static const struct i2c_algorithm riic_algo = {
>>
>> static int riic_init_hw(struct riic_dev *riic, struct i2c_timings *t) {
>> + int ret;
>> unsigned long rate;
>> int total_ticks, cks, brl, brh;
>> struct device *dev = riic->adapter.dev.parent; @@ -379,7 +386,11 @@ static int
>> riic_init_hw(struct riic_dev *riic, struct i2c_timings *t)
>> t->scl_fall_ns / (1000000000 / rate),
>> t->scl_rise_ns / (1000000000 / rate), cks, brl, brh);
>>
>> - pm_runtime_get_sync(dev);
>> + ret = pm_runtime_resume_and_get(dev);
>> + if (ret) {
>> + dev_err(dev, riic_rpm_err_msg);
>> + return ret;
>> + }
>>
>> /* Changing the order of accessing IICRST and ICE may break things! */
>> riic_writeb(riic, ICCR1_IICRST | ICCR1_SOWP, RIIC_ICCR1); @@ -498,11 +509,18 @@ static void
>> riic_i2c_remove(struct platform_device *pdev) {
>> struct riic_dev *riic = platform_get_drvdata(pdev);
>> struct device *dev = &pdev->dev;
>> + int ret;
>>
>> - pm_runtime_get_sync(dev);
>> - riic_writeb(riic, 0, RIIC_ICIER);
>> - pm_runtime_put(dev);
>> i2c_del_adapter(&riic->adapter);
>> +
>> + ret = pm_runtime_resume_and_get(dev);
>> + if (ret) {
>> + dev_err(dev, riic_rpm_err_msg);
>> + } else {
>> + riic_writeb(riic, 0, RIIC_ICIER);
>> + pm_runtime_put(dev);
>> + }
>> +
>> pm_runtime_disable(dev);
>> }
>>
>> --
>> 2.39.2
>>
>
