Re: [PATCH v5 1/2] gpio: add GPO driver for PCA9570

2020-07-08 Thread Sungbo Eo
Thanks, it made me think about it deeper... On 20. 7. 8. 오전 12:07, Andy Shevchenko wrote: On Tue, Jul 7, 2020 at 5:03 PM Sungbo Eo wrote: On 20. 7. 6. 오후 9:00, Andy Shevchenko wrote: ... But I don't really understand what mutex does here. The driver does not need consecutive commands, it o

Re: [PATCH v5 1/2] gpio: add GPO driver for PCA9570

2020-07-07 Thread Andy Shevchenko
On Tue, Jul 7, 2020 at 5:03 PM Sungbo Eo wrote: > On 20. 7. 6. 오후 9:00, Andy Shevchenko wrote: ... > But I don't really understand what mutex does here. The driver does not > need consecutive commands, it only sends/receives only one byte at a > time. And AFAIK each i2c_smbus function is already

Re: [PATCH v5 1/2] gpio: add GPO driver for PCA9570

2020-07-07 Thread Sungbo Eo
On 20. 7. 6. 오후 9:00, Andy Shevchenko wrote: On Mon, Jul 6, 2020 at 2:21 PM Bartosz Golaszewski wrote:> On Sun, Jul 5, 2020 at 3:31 PM Sungbo Eo wrote: NXP PCA9570 is a 4-bit I2C GPO expander without interrupt functionality. Its ports are controlled only by a data byte without register addre

Re: [PATCH v5 1/2] gpio: add GPO driver for PCA9570

2020-07-06 Thread Andy Shevchenko
On Sun, Jul 5, 2020 at 4:31 PM Sungbo Eo wrote: > > NXP PCA9570 is a 4-bit I2C GPO expander without interrupt functionality. > Its ports are controlled only by a data byte without register address. Thank you for an update, my comments (besides what Bart has) below. > Datasheet: https://www.nxp.c

Re: [PATCH v5 1/2] gpio: add GPO driver for PCA9570

2020-07-06 Thread Andy Shevchenko
On Mon, Jul 6, 2020 at 2:21 PM Bartosz Golaszewski wrote:> > On Sun, Jul 5, 2020 at 3:31 PM Sungbo Eo wrote: > > > > NXP PCA9570 is a 4-bit I2C GPO expander without interrupt functionality. > > Its ports are controlled only by a data byte without register address. > > > > Datasheet: https://www.

Re: [PATCH v5 1/2] gpio: add GPO driver for PCA9570

2020-07-06 Thread Bartosz Golaszewski
On Sun, Jul 5, 2020 at 3:31 PM Sungbo Eo wrote: > > NXP PCA9570 is a 4-bit I2C GPO expander without interrupt functionality. > Its ports are controlled only by a data byte without register address. > > Datasheet: https://www.nxp.com/docs/en/data-sheet/PCA9570.pdf > > Signed-off-by: Sungbo Eo > --

[PATCH v5 1/2] gpio: add GPO driver for PCA9570

2020-07-05 Thread Sungbo Eo
NXP PCA9570 is a 4-bit I2C GPO expander without interrupt functionality. Its ports are controlled only by a data byte without register address. Datasheet: https://www.nxp.com/docs/en/data-sheet/PCA9570.pdf Signed-off-by: Sungbo Eo --- v5: * amended the commit message * removed unnecessary castin