public inbox for linux-kernel@vger.kernel.org
 help / color / mirror / Atom feed
* [PATCH] GPIO/TCA6424: merge I2C transactions, remove cast
@ 2012-05-18 15:01 Andreas Schallenberg
  2012-05-18 23:44 ` Grant Likely
  0 siblings, 1 reply; 3+ messages in thread
From: Andreas Schallenberg @ 2012-05-18 15:01 UTC (permalink / raw)
  To: grant.likely, linus.walleij, linux-kernel

>From 1a80280e20dfef57c6bc6429e5bdf7e10d10fda9 Mon Sep 17 00:00:00 2001
From: Andreas Schallenberg <Andreas.Schallenberg@3alitytechnica.com>
Date: Fri, 18 May 2012 16:20:31 +0200
Subject: [PATCH] GPIO/TCA6424: merge I2C transactions, remove cast

This is a follow-up to "[PATCH v2] Add support for TCA6424":
- Use 3 byte transfers instead of two separate transfers (2+1 byte)
- An unnecessary cast removed

Please check especially if endianness conversion is done the way it should be.

Signed-off-by: Andreas Schallenberg <Andreas.Schallenberg@3alitytechnica.com>

---
 drivers/gpio/gpio-pca953x.c |   27 ++++++++++++++++-----------
 1 files changed, 16 insertions(+), 11 deletions(-)

diff --git a/drivers/gpio/gpio-pca953x.c b/drivers/gpio/gpio-pca953x.c
index 1c313c7..5eee524 100644
--- a/drivers/gpio/gpio-pca953x.c
+++ b/drivers/gpio/gpio-pca953x.c
@@ -98,12 +98,11 @@ static int pca953x_write_reg(struct pca953x_chip *chip, 
int reg, u32 val)
        if (chip->gpio_chip.ngpio <= 8)
                ret = i2c_smbus_write_byte_data(chip->client, reg, val);
        else if (chip->gpio_chip.ngpio == 24) {
-               ret = i2c_smbus_write_word_data(chip->client,
+               cpu_to_le32s(&val);
+               ret = i2c_smbus_write_i2c_block_data(chip->client,
                                                (reg << 2) | REG_ADDR_AI,
-                                               val & 0xffff);
-               ret = i2c_smbus_write_byte_data(chip->client,
-                                               (reg << 2) + 2,
-                                               (val & 0xff0000) >> 16);
+                                               3,
+                                               (u8 *) &val);
        }
        else {
                switch (chip->chip_type) {
@@ -135,22 +134,28 @@ static int pca953x_read_reg(struct pca953x_chip *chip, 
int reg, u32 *val)
 {
        int ret;
 
-       if (chip->gpio_chip.ngpio <= 8)
+       if (chip->gpio_chip.ngpio <= 8) {
                ret = i2c_smbus_read_byte_data(chip->client, reg);
+               *val = ret;
+       }
        else if (chip->gpio_chip.ngpio == 24) {
-               ret =  i2c_smbus_read_word_data(chip->client, reg << 2);
-               ret |= (i2c_smbus_read_byte_data(chip->client,
-                                                (reg << 2) + 2)<<16);
+               *val = 0;
+               ret = i2c_smbus_read_i2c_block_data(chip->client,
+                                               (reg << 2) | REG_ADDR_AI,
+                                               3,
+                                               (u8 *) val);
+               le32_to_cpus(val);
        }
-       else
+       else {
                ret = i2c_smbus_read_word_data(chip->client, reg << 1);
+               *val = ret;
+       }
 
        if (ret < 0) {
                dev_err(&chip->client->dev, "failed reading register\n");
                return ret;
        }
 
-       *val = (u32)ret;
        return 0;
 }
 
-- 
1.7.3.4

^ permalink raw reply related	[flat|nested] 3+ messages in thread

* Re: [PATCH] GPIO/TCA6424: merge I2C transactions, remove cast
  2012-05-18 15:01 [PATCH] GPIO/TCA6424: merge I2C transactions, remove cast Andreas Schallenberg
@ 2012-05-18 23:44 ` Grant Likely
  2012-05-18 23:47   ` Grant Likely
  0 siblings, 1 reply; 3+ messages in thread
From: Grant Likely @ 2012-05-18 23:44 UTC (permalink / raw)
  To: Andreas Schallenberg, linus.walleij, linux-kernel

On Fri, 18 May 2012 17:01:36 +0200, Andreas Schallenberg <Andreas.Schallenberg@3alitytechnica.com> wrote:
> From 1a80280e20dfef57c6bc6429e5bdf7e10d10fda9 Mon Sep 17 00:00:00 2001
> From: Andreas Schallenberg <Andreas.Schallenberg@3alitytechnica.com>
> Date: Fri, 18 May 2012 16:20:31 +0200
> Subject: [PATCH] GPIO/TCA6424: merge I2C transactions, remove cast
> 
> This is a follow-up to "[PATCH v2] Add support for TCA6424":
> - Use 3 byte transfers instead of two separate transfers (2+1 byte)
> - An unnecessary cast removed
> 
> Please check especially if endianness conversion is done the way it should be.

It works I suppose.  Personally, I'd explicitly use a byte array, but
I'll apply this patch as-is anyway.

g.

> 
> Signed-off-by: Andreas Schallenberg <Andreas.Schallenberg@3alitytechnica.com>
> 
> ---
>  drivers/gpio/gpio-pca953x.c |   27 ++++++++++++++++-----------
>  1 files changed, 16 insertions(+), 11 deletions(-)
> 
> diff --git a/drivers/gpio/gpio-pca953x.c b/drivers/gpio/gpio-pca953x.c
> index 1c313c7..5eee524 100644
> --- a/drivers/gpio/gpio-pca953x.c
> +++ b/drivers/gpio/gpio-pca953x.c
> @@ -98,12 +98,11 @@ static int pca953x_write_reg(struct pca953x_chip *chip, 
> int reg, u32 val)
>         if (chip->gpio_chip.ngpio <= 8)
>                 ret = i2c_smbus_write_byte_data(chip->client, reg, val);
>         else if (chip->gpio_chip.ngpio == 24) {
> -               ret = i2c_smbus_write_word_data(chip->client,
> +               cpu_to_le32s(&val);
> +               ret = i2c_smbus_write_i2c_block_data(chip->client,
>                                                 (reg << 2) | REG_ADDR_AI,
> -                                               val & 0xffff);
> -               ret = i2c_smbus_write_byte_data(chip->client,
> -                                               (reg << 2) + 2,
> -                                               (val & 0xff0000) >> 16);
> +                                               3,
> +                                               (u8 *) &val);
>         }
>         else {
>                 switch (chip->chip_type) {
> @@ -135,22 +134,28 @@ static int pca953x_read_reg(struct pca953x_chip *chip, 
> int reg, u32 *val)
>  {
>         int ret;
>  
> -       if (chip->gpio_chip.ngpio <= 8)
> +       if (chip->gpio_chip.ngpio <= 8) {
>                 ret = i2c_smbus_read_byte_data(chip->client, reg);
> +               *val = ret;
> +       }
>         else if (chip->gpio_chip.ngpio == 24) {
> -               ret =  i2c_smbus_read_word_data(chip->client, reg << 2);
> -               ret |= (i2c_smbus_read_byte_data(chip->client,
> -                                                (reg << 2) + 2)<<16);
> +               *val = 0;
> +               ret = i2c_smbus_read_i2c_block_data(chip->client,
> +                                               (reg << 2) | REG_ADDR_AI,
> +                                               3,
> +                                               (u8 *) val);
> +               le32_to_cpus(val);
>         }
> -       else
> +       else {
>                 ret = i2c_smbus_read_word_data(chip->client, reg << 1);
> +               *val = ret;
> +       }
>  
>         if (ret < 0) {
>                 dev_err(&chip->client->dev, "failed reading register\n");
>                 return ret;
>         }
>  
> -       *val = (u32)ret;
>         return 0;
>  }
>  
> -- 
> 1.7.3.4
> --
> To unsubscribe from this list: send the line "unsubscribe linux-kernel" in
> the body of a message to majordomo@vger.kernel.org
> More majordomo info at  http://vger.kernel.org/majordomo-info.html
> Please read the FAQ at  http://www.tux.org/lkml/

-- 
Grant Likely, B.Sc, P.Eng.
Secret Lab Technologies, Ltd.

^ permalink raw reply	[flat|nested] 3+ messages in thread

* Re: [PATCH] GPIO/TCA6424: merge I2C transactions, remove cast
  2012-05-18 23:44 ` Grant Likely
@ 2012-05-18 23:47   ` Grant Likely
  0 siblings, 0 replies; 3+ messages in thread
From: Grant Likely @ 2012-05-18 23:47 UTC (permalink / raw)
  To: Andreas Schallenberg, linus.walleij, linux-kernel

On Fri, 18 May 2012 17:44:10 -0600, Grant Likely <grant.likely@secretlab.ca> wrote:
> On Fri, 18 May 2012 17:01:36 +0200, Andreas Schallenberg <Andreas.Schallenberg@3alitytechnica.com> wrote:
> > From 1a80280e20dfef57c6bc6429e5bdf7e10d10fda9 Mon Sep 17 00:00:00 2001
> > From: Andreas Schallenberg <Andreas.Schallenberg@3alitytechnica.com>
> > Date: Fri, 18 May 2012 16:20:31 +0200
> > Subject: [PATCH] GPIO/TCA6424: merge I2C transactions, remove cast
> > 
> > This is a follow-up to "[PATCH v2] Add support for TCA6424":
> > - Use 3 byte transfers instead of two separate transfers (2+1 byte)
> > - An unnecessary cast removed
> > 
> > Please check especially if endianness conversion is done the way it should be.
> 
> It works I suppose.  Personally, I'd explicitly use a byte array, but
> I'll apply this patch as-is anyway.

Patch is damaged and cannot be applied (line wraps and tabs converted
to spaces).  Please check your mailer (please use git send-email) and
repost.

g.


^ permalink raw reply	[flat|nested] 3+ messages in thread

end of thread, other threads:[~2012-05-18 23:47 UTC | newest]

Thread overview: 3+ messages (download: mbox.gz follow: Atom feed
-- links below jump to the message on this page --
2012-05-18 15:01 [PATCH] GPIO/TCA6424: merge I2C transactions, remove cast Andreas Schallenberg
2012-05-18 23:44 ` Grant Likely
2012-05-18 23:47   ` Grant Likely

This is a public inbox, see mirroring instructions
for how to clone and mirror all data and code used for this inbox