Re: [PATCH] media: atomisp: Use clamp_t() in ia_css_eed1_8_vmem_encode()

[Hans de Goede <hdegoede@redhat.com>]

Hi Mauro,

On 9/6/24 8:15 AM, Mauro Carvalho Chehab wrote:
> Em Sat, 27 Jul 2024 14:51:56 +0200
> Christophe JAILLET <christophe.jaillet@wanadoo.fr> escreveu:
> 
>> Using clamp_t() instead of min_t(max_t()) is easier to read.
>>
>> It also reduces the size of the preprocessed files by ~ 193 ko.
>> (see [1] for a discussion about it)
>>
>> $ ls -l ia_css_eed1_8.host*.i
>>  4829993 27 juil. 14:36 ia_css_eed1_8.host.old.i
>>  4636649 27 juil. 14:42 ia_css_eed1_8.host.new.i
>>
>> [1]: https://lore.kernel.org/all/23bdb6fc8d884ceebeb6e8b8653b8cfe@AcuMS.aculab.com/
>>
>> Signed-off-by: Christophe JAILLET <christophe.jaillet@wanadoo.fr>
>> ---
>>  .../isp/kernels/eed1_8/ia_css_eed1_8.host.c   | 24 +++++++++----------
>>  1 file changed, 12 insertions(+), 12 deletions(-)
>>
>> diff --git a/drivers/staging/media/atomisp/pci/isp/kernels/eed1_8/ia_css_eed1_8.host.c b/drivers/staging/media/atomisp/pci/isp/kernels/eed1_8/ia_css_eed1_8.host.c
>> index e4fc90f88e24..96c13ebc4331 100644
>> --- a/drivers/staging/media/atomisp/pci/isp/kernels/eed1_8/ia_css_eed1_8.host.c
>> +++ b/drivers/staging/media/atomisp/pci/isp/kernels/eed1_8/ia_css_eed1_8.host.c
>> @@ -172,25 +172,25 @@ ia_css_eed1_8_vmem_encode(
>>  		base = shuffle_block * i;
>>  
>>  		for (j = 0; j < IA_CSS_NUMBER_OF_DEW_ENHANCE_SEGMENTS; j++) {
>> -			to->e_dew_enh_x[0][base + j] = min_t(int, max_t(int,
>> -							     from->dew_enhance_seg_x[j], 0),
>> -							     8191);
>> -			to->e_dew_enh_y[0][base + j] = min_t(int, max_t(int,
>> -							     from->dew_enhance_seg_y[j], -8192),
>> -							     8191);
>> +			to->e_dew_enh_x[0][base + j] = clamp_t(int,
>> +							       from->dew_enhance_seg_x[j],
>> +							       0, 8191);
>> +			to->e_dew_enh_y[0][base + j] = clamp_t(int,
>> +							       from->dew_enhance_seg_y[j],
>> +							       -8192, 8191);
> 
> Such change introduces two warnings on smatch:
> 
> drivers/staging/media/atomisp/pci/isp/kernels/eed1_8/ia_css_eed1_8.host.c: drivers/staging/media/atomisp/pci/isp/kernels/eed1_8/ia_css_eed1_8.host.c:177 ia_css_eed1_8_vmem_encode() warn: assigning (-8192) to unsigned variable 'to->e_dew_enh_y[0][base + j]'
> drivers/staging/media/atomisp/pci/isp/kernels/eed1_8/ia_css_eed1_8.host.c: drivers/staging/media/atomisp/pci/isp/kernels/eed1_8/ia_css_eed1_8.host.c:182 ia_css_eed1_8_vmem_encode() warn: assigning (-8192) to unsigned variable 'to->e_dew_enh_a[0][base + j]'
> 
> Should dew_enhance_seg_x and dew_enhance_seg_y be converted to signed?

These already are s32, the problem is that e_dew_enh_a is of type t_vmem_elem which is:

typedef u16 t_vmem_elem;

And that type is used in a lot of places, so we cannot
just change that.

I guess we could add a t_signed_vmem_elem (s16) and use that for these vmem-arrays ?

I tried fixing it like this:

diff --git a/drivers/staging/media/atomisp/i2c/atomisp-t4ka3.c b/drivers/staging/media/atomisp/i2c/atomisp-t4ka3.c
index 1e01d354152b..7c0195d15f53 100644
--- a/drivers/staging/media/atomisp/i2c/atomisp-t4ka3.c
+++ b/drivers/staging/media/atomisp/i2c/atomisp-t4ka3.c
@@ -428,18 +428,13 @@ static int t4ka3_s_stream(struct v4l2_subdev *sd, int enable)
 			goto error_unlock;
 		}
 
-		ret = cci_multi_reg_write(sensor->regmap, t4ka3_init_config,
-					  ARRAY_SIZE(t4ka3_init_config), NULL);
-		if (ret)
-			goto error_powerdown;
-
+		cci_multi_reg_write(sensor->regmap, t4ka3_init_config,
+				    ARRAY_SIZE(t4ka3_init_config), &ret);
 		/* enable group hold */
-		ret = cci_multi_reg_write(sensor->regmap, t4ka3_param_hold,
-					  ARRAY_SIZE(t4ka3_param_hold), NULL);
-		if (ret)
-			goto error_powerdown;
-
-		ret = cci_multi_reg_write(sensor->regmap, sensor->res->regs, sensor->res->regs_len, NULL);
+		cci_multi_reg_write(sensor->regmap, t4ka3_param_hold,
+				    ARRAY_SIZE(t4ka3_param_hold), &ret);
+		cci_multi_reg_write(sensor->regmap, sensor->res->regs,
+				    sensor->res->regs_len, &ret);
 		if (ret)
 			goto error_powerdown;
 
diff --git a/drivers/staging/media/atomisp/pci/isp/kernels/eed1_8/ia_css_eed1_8.host.c b/drivers/staging/media/atomisp/pci/isp/kernels/eed1_8/ia_css_eed1_8.host.c
index b79d78e5b77f..c9043d516192 100644
--- a/drivers/staging/media/atomisp/pci/isp/kernels/eed1_8/ia_css_eed1_8.host.c
+++ b/drivers/staging/media/atomisp/pci/isp/kernels/eed1_8/ia_css_eed1_8.host.c
@@ -172,21 +172,21 @@ ia_css_eed1_8_vmem_encode(
 		base = shuffle_block * i;
 
 		for (j = 0; j < IA_CSS_NUMBER_OF_DEW_ENHANCE_SEGMENTS; j++) {
-			to->e_dew_enh_x[0][base + j] = clamp(from->dew_enhance_seg_x[j],
-							     0, 8191);
-			to->e_dew_enh_y[0][base + j] = clamp(from->dew_enhance_seg_y[j],
-							     -8192, 8191);
+			to->e_dew_enh_x[0][base + j] = (u16)clamp(from->dew_enhance_seg_x[j],
+								  0, 8191);
+			to->e_dew_enh_y[0][base + j] = (u16)clamp(from->dew_enhance_seg_y[j],
+								  -8192, 8191);
 		}
 
 		for (j = 0; j < (IA_CSS_NUMBER_OF_DEW_ENHANCE_SEGMENTS - 1); j++) {
-			to->e_dew_enh_a[0][base + j] = clamp(from->dew_enhance_seg_slope[j],
-							     -8192, 8191);
+			to->e_dew_enh_a[0][base + j] = (u16)clamp(from->dew_enhance_seg_slope[j],
+								  -8192, 8191);
 			/* Convert dew_enhance_seg_exp to flag:
 			 * 0 -> 0
 			 * 1...13 -> 1
 			 */
-			to->e_dew_enh_f[0][base + j] = clamp(from->dew_enhance_seg_exp[j],
-							     0, 13) > 0;
+			to->e_dew_enh_f[0][base + j] = (u16)clamp(from->dew_enhance_seg_exp[j],
+								  0, 13) > 0;
 		}
 
 		/* Hard-coded to 0, in order to be able to handle out of

but smatch still complains after this...

Regards,

Hans