On Sun, Oct 28, 2018 at 02:36:07PM +0000, Jonathan Cameron wrote:
> On Sun, 28 Oct 2018 13:21:25 +0530
> Nishad Kamdar <nishadkam...@gmail.com> wrote:
> 
> > Use the gpiod interface instead of the deprecated old non-descriptor
> > interface.
> > 
> > Signed-off-by: Nishad Kamdar <nishadkam...@gmail.com>
> Hi Nishad,
> 
> Sorry it took me most of the week to get to this.  It's a trade off when you
> want to make fast progress, but I would suggest always leaving a few days
> between patches to see if there are other review comments coming in.
>

Ok, I'll keep that in mind.
> I don't particularly mind myself (as I'm very good at ignoring older versions 
> ;)
> but I do feel some time got wasted here on your part.
> 
> Anyhow, what you have here is correct but the drive to get things as a nice
> array has lead to a weird mixture of being all array based and not being at 
> all.
> Some suggestions in line that will hopefully tidy this up for you.
> 
> I'm basically suggesting adding a layer of indirection where you don't 
> currently
> have one (on the actual reads and writes) so that you get more consistency
> with the setup code rather than adding a lot of fiddly indirection just in
> the setup code.
> 
> Note, what I've given is very much meant to be an illustration.  It's probably
> full of bugs and silly naming etc, so don't take it as being right!
> 
> Jonathan
> 
> > ---
> >  drivers/staging/iio/resolver/ad2s1210.c | 92 ++++++++++++++-----------
> >  drivers/staging/iio/resolver/ad2s1210.h |  3 -
> >  2 files changed, 50 insertions(+), 45 deletions(-)
> > 
> > diff --git a/drivers/staging/iio/resolver/ad2s1210.c 
> > b/drivers/staging/iio/resolver/ad2s1210.c
> > index ac13b99bd9cb..93c3c70ce62e 100644
> > --- a/drivers/staging/iio/resolver/ad2s1210.c
> > +++ b/drivers/staging/iio/resolver/ad2s1210.c
> > @@ -15,7 +15,7 @@
> >  #include <linux/slab.h>
> >  #include <linux/sysfs.h>
> >  #include <linux/delay.h>
> > -#include <linux/gpio.h>
> > +#include <linux/gpio/consumer.h>
> >  #include <linux/module.h>
> >  
> >  #include <linux/iio/iio.h>
> > @@ -69,10 +69,21 @@ enum ad2s1210_mode {
> >  
> >  static const unsigned int ad2s1210_resolution_value[] = { 10, 12, 14, 16 };
> >  
> > +struct ad2s1210_gpio {
> > +   struct gpio_desc **ptr;
> > +   const char *name;
> > +   unsigned long flags;
> > +};
> > +
> >  struct ad2s1210_state {
> >     const struct ad2s1210_platform_data *pdata;
> >     struct mutex lock;
> >     struct spi_device *sdev;
> 
> With the setup below this becomes
>       struct gpio_desc *gpios[5];
> 
> > +   struct gpio_desc *sample;
> > +   struct gpio_desc *a0;
> > +   struct gpio_desc *a1;
> > +   struct gpio_desc *res0;
> > +   struct gpio_desc *res1;
> >     unsigned int fclkin;
> >     unsigned int fexcit;
> >     bool hysteresis;
> > @@ -91,8 +102,8 @@ static const int ad2s1210_mode_vals[4][2] = {
> >  static inline void ad2s1210_set_mode(enum ad2s1210_mode mode,
> >                                  struct ad2s1210_state *st)
> >  {
> > -   gpio_set_value(st->pdata->a[0], ad2s1210_mode_vals[mode][0]);
> > -   gpio_set_value(st->pdata->a[1], ad2s1210_mode_vals[mode][1]);
> > +   gpiod_set_value(st->a0, ad2s1210_mode_vals[mode][0]);
> > +   gpiod_set_value(st->a1, ad2s1210_mode_vals[mode][1]);
> >     st->mode = mode;
> >  }
> >  
> > @@ -152,8 +163,8 @@ int ad2s1210_update_frequency_control_word(struct 
> > ad2s1210_state *st)
> >  
> >  static unsigned char ad2s1210_read_resolution_pin(struct ad2s1210_state 
> > *st)
> >  {
> > -   int resolution = (gpio_get_value(st->pdata->res[0]) << 1) |
> > -                     gpio_get_value(st->pdata->res[1]);
> > +   int resolution = (gpiod_get_value(st->res0) << 1) |
> > +                     gpiod_get_value(st->res1);
> >  
> >     return ad2s1210_resolution_value[resolution];
> >  }
> > @@ -164,10 +175,10 @@ static const int ad2s1210_res_pins[4][2] = {
> >  
> >  static inline void ad2s1210_set_resolution_pin(struct ad2s1210_state *st)
> >  {
> > -   gpio_set_value(st->pdata->res[0],
> > -                  ad2s1210_res_pins[(st->resolution - 10) / 2][0]);
> > -   gpio_set_value(st->pdata->res[1],
> > -                  ad2s1210_res_pins[(st->resolution - 10) / 2][1]);
> > +   gpiod_set_value(st->res0,
> > +                   ad2s1210_res_pins[(st->resolution - 10) / 2][0]);
> > +   gpiod_set_value(st->res1,
> > +                   ad2s1210_res_pins[(st->resolution - 10) / 2][1]);
> >  }
> >  
> >  static inline int ad2s1210_soft_reset(struct ad2s1210_state *st)
> > @@ -401,15 +412,15 @@ static ssize_t ad2s1210_clear_fault(struct device 
> > *dev,
> >     int ret;
> >  
> >     mutex_lock(&st->lock);
> > -   gpio_set_value(st->pdata->sample, 0);
> > +   gpiod_set_value(st->sample, 0);
> >     /* delay (2 * tck + 20) nano seconds */
> >     udelay(1);
> > -   gpio_set_value(st->pdata->sample, 1);
> > +   gpiod_set_value(st->sample, 1);
> >     ret = ad2s1210_config_read(st, AD2S1210_REG_FAULT);
> >     if (ret < 0)
> >             goto error_ret;
> > -   gpio_set_value(st->pdata->sample, 0);
> > -   gpio_set_value(st->pdata->sample, 1);
> > +   gpiod_set_value(st->sample, 0);
> > +   gpiod_set_value(st->sample, 1);
> >  error_ret:
> >     mutex_unlock(&st->lock);
> >  
> > @@ -466,7 +477,7 @@ static int ad2s1210_read_raw(struct iio_dev *indio_dev,
> >     s16 vel;
> >  
> >     mutex_lock(&st->lock);
> > -   gpio_set_value(st->pdata->sample, 0);
> > +   gpiod_set_value(st->sample, 0);
> >     /* delay (6 * tck + 20) nano seconds */
> >     udelay(1);
> >  
> > @@ -512,7 +523,7 @@ static int ad2s1210_read_raw(struct iio_dev *indio_dev,
> >     }
> >  
> >  error_ret:
> > -   gpio_set_value(st->pdata->sample, 1);
> > +   gpiod_set_value(st->sample, 1);
> 
> With the below this becomes
>       gpiod_set_value(st->gpios[AD2S1210_SAMPLE], 1);
> 
> >     /* delay (2 * tck + 20) nano seconds */
> >     udelay(1);
> >     mutex_unlock(&st->lock);
> > @@ -630,30 +641,32 @@ static const struct iio_info ad2s1210_info = {
> >  
> >  static int ad2s1210_setup_gpios(struct ad2s1210_state *st)
> >  {
> > -   unsigned long flags = st->pdata->gpioin ? GPIOF_DIR_IN : GPIOF_DIR_OUT;
> > -   struct gpio ad2s1210_gpios[] = {
> > -           { st->pdata->sample, GPIOF_DIR_IN, "sample" },
> > -           { st->pdata->a[0], flags, "a0" },
> > -           { st->pdata->a[1], flags, "a1" },
> > -           { st->pdata->res[0], flags, "res0" },
> > -           { st->pdata->res[0], flags, "res1" },
> > +   int ret, i;
> > +   struct spi_device *spi = st->sdev;
> > +   struct ad2s1210_gpio *pin;
> > +   unsigned long flags = st->pdata->gpioin ? GPIOD_IN : GPIOD_OUT_LOW;
> 
> So talk me through what is going on here?  All of a and res are controlled
> by this one parameter?
>

Yes. This was how the original code was. I kept it as it is.
> > +
> > +   struct ad2s1210_gpio gpios[] = {
> > +           { .ptr = &st->sample, .name = "sample", .flags = GPIOD_IN },
> > +           { .ptr = &st->a0, .name = "a0", .flags = flags },
> > +           { .ptr = &st->a1, .name = "a1", .flags = flags },
> > +           { .ptr = &st->res0, .name = "res0", .flags = flags },
> > +           { .ptr = &st->res1, .name = "res1", .flags = flags },
> 
> To my eye, there are two sets of gpios in here.  They were originally handled
> like that st->pdata->a[0] etc, and it would be sensible to continue doing so.
> 
> Actually I don't really like the indirection at all.  Why not have
> a simple enum indexing the gpios and then have a single array in st for them 
> all?
> 
> enum ad2s1210_gpios {
>       AD2S1210_SAMPLE,
>       AD2S1210_A0,
>       AD2S1210_A1,
>       AD2S1210_RES0,
>       AD2S1210_RES1,
> };
> 
> Then have two constant versions of the above structure (shrunk a bit) that you
> pick from depending on the flag.
> 
> static const struct ad2s1210_gpio gpios_gpioin[] = {
>       [AD2S1210_SAMPLE] = { .name = "sample", .flags = GPIOD_IN, },
>       [AD2S1210_A0] = { .name = "a0", .flags = GPIOD_IN, },
>       [AD2S1210_A1] = { .name = "a1", .flags = GPIOD_IN, },
>       [AD2S1210_RES0] = { .name = "res0", .flags = GPIOD_IN, },
>       [AD2S1210_RES1] = { .name = "res1", .flags = GPIOD_IN, },
> };
> 
> static const struct ad2s1210_gpio gpios_gpioout[] = {
>       [AD2S1210_SAMPLE] = { .name = "sample", .flags = GPIOD_IN, },
>       [AD2S1210_A0] = { .name = "a0", .flags = GPIOD_OUT, },
>       [AD2S1210_A1] = { .name = "a1", .flags = GPIOD_OUT, },
>       [AD2S1210_RES0] = { .name = "res0", .flags = GPIOD_OUT, },
>       [AD2S1210_RES1] = { .name = "res1", .flags = GPIOD_OUT, },
> };
> 
> 
> static int ad2s1210_setup_gpios(struct ad2s1210_state *st, bool gpioin)
> {
> //note my naming is awful so do this better than I have ;)
>       struct ad2s1201_gpio *pin = gpioin ? &gpios_gpioin[0] : 
> &gpios_gpiout[0]; 
>       int i;
> 
> 
>       for (i = 0; i < ARRAY_SIZE(gpios_gpioin); i++) {
>               st->gpios[i] = devm_gpiod_get(&spi->dev, pin[i]->name, 
> pin[i]->flags);
>               if (IS_ERR(st->gpios[i])) {
>                       ret = PTR_ERR(st->gpios[i]);
>                       dev_err(&spi->dev,
>                               "ad2s1210: failed to request %s GPIO: %d\n",
>                               pin->name, ret);
>                       return ret;
>               }
>       }
> 
>       return 0;
> }
> 
> >     };
> >  
> > -   return gpio_request_array(ad2s1210_gpios, ARRAY_SIZE(ad2s1210_gpios));
> > -}
> > -
> > -static void ad2s1210_free_gpios(struct ad2s1210_state *st)
> > -{
> > -   unsigned long flags = st->pdata->gpioin ? GPIOF_DIR_IN : GPIOF_DIR_OUT;
> > -   struct gpio ad2s1210_gpios[] = {
> > -           { st->pdata->sample, GPIOF_DIR_IN, "sample" },
> > -           { st->pdata->a[0], flags, "a0" },
> > -           { st->pdata->a[1], flags, "a1" },
> > -           { st->pdata->res[0], flags, "res0" },
> > -           { st->pdata->res[0], flags, "res1" },
> > -   };
> > +   for (i = 0; i < ARRAY_SIZE(gpios); i++) {
> > +           pin = &gpios[i];
> > +           *pin->ptr = devm_gpiod_get(&spi->dev, pin->name, pin->flags);
> > +           if (IS_ERR(*pin->ptr)) {
> > +                   ret = PTR_ERR(*pin->ptr);
> > +                   dev_err(&spi->dev,
> > +                           "ad2s1210: failed to request %s GPIO: %d\n",
> > +                           pin->name, ret);
> > +                   return ret;
> > +           }
> > +   }
> >  
> > -   gpio_free_array(ad2s1210_gpios, ARRAY_SIZE(ad2s1210_gpios));
> > +   return 0;
> >  }
> >  
> >  static int ad2s1210_probe(struct spi_device *spi)
> > @@ -692,7 +705,7 @@ static int ad2s1210_probe(struct spi_device *spi)
> >  
> >     ret = iio_device_register(indio_dev);
> >     if (ret)
> > -           goto error_free_gpios;
> > +           return ret;
> >  
> >     st->fclkin = spi->max_speed_hz;
> >     spi->mode = SPI_MODE_3;
> > @@ -700,10 +713,6 @@ static int ad2s1210_probe(struct spi_device *spi)
> >     ad2s1210_initial(st);
> >  
> >     return 0;
> > -
> > -error_free_gpios:
> > -   ad2s1210_free_gpios(st);
> > -   return ret;
> >  }
> >  
> >  static int ad2s1210_remove(struct spi_device *spi)
> > @@ -711,7 +720,6 @@ static int ad2s1210_remove(struct spi_device *spi)
> >     struct iio_dev *indio_dev = spi_get_drvdata(spi);
> >  
> >     iio_device_unregister(indio_dev);
> > -   ad2s1210_free_gpios(iio_priv(indio_dev));
> >  
> >     return 0;
> >  }
> > diff --git a/drivers/staging/iio/resolver/ad2s1210.h 
> > b/drivers/staging/iio/resolver/ad2s1210.h
> > index e9b2147701fc..63d479b20a6c 100644
> > --- a/drivers/staging/iio/resolver/ad2s1210.h
> > +++ b/drivers/staging/iio/resolver/ad2s1210.h
> > @@ -12,9 +12,6 @@
> >  #define _AD2S1210_H
> >  
> >  struct ad2s1210_platform_data {
> > -   unsigned int            sample;
> > -   unsigned int            a[2];
> > -   unsigned int            res[2];
> >     bool                    gpioin;
> >  };
> >  #endif /* _AD2S1210_H */
> 

ok, I'll make the changes.

Thanks for thre review.

regards,
Nishad
_______________________________________________
devel mailing list
de...@linuxdriverproject.org
http://driverdev.linuxdriverproject.org/mailman/listinfo/driverdev-devel

Reply via email to