[PATCH] nvmem: qfprom: Fix to support single byte read/write

[PATCH] nvmem: qfprom: Fix to support single byte read/write

[Vivek Gautam]

The nvmem core driver supports to read and write single
byte. This helps in extracting a required value based
on bit-offset and number of bits for the required value
in the nvmem cell.

Signed-off-by: Vivek Gautam <vivek.gautam@codeaurora.org>
---

Based on torvalds's master branch.

 - Tested on db410c for thermal sensors, and
   on db820c for qusb2 phy with tree [1] based on linaro qcom landing
   team's integration tree.

[1] https://github.com/vivekgautam1/linux/tree/linaro/integration-linux-qcomlt-qcom-phy-upstream

 drivers/nvmem/qfprom.c | 14 +++++++-------
 1 file changed, 7 insertions(+), 7 deletions(-)

diff --git a/drivers/nvmem/qfprom.c b/drivers/nvmem/qfprom.c
index b5305f0..2bdb6c3 100644
--- a/drivers/nvmem/qfprom.c
+++ b/drivers/nvmem/qfprom.c
@@ -21,11 +21,11 @@ static int qfprom_reg_read(void *context,
 			unsigned int reg, void *_val, size_t bytes)
 {
 	void __iomem *base = context;
-	u32 *val = _val;
-	int i = 0, words = bytes / 4;
+	u8 *val = _val;
+	int i = 0, words = bytes;
 
 	while (words--)
-		*val++ = readl(base + reg + (i++ * 4));
+		*val++ = readb(base + reg + i++);
 
 	return 0;
 }
@@ -34,11 +34,11 @@ static int qfprom_reg_write(void *context,
 			 unsigned int reg, void *_val, size_t bytes)
 {
 	void __iomem *base = context;
-	u32 *val = _val;
-	int i = 0, words = bytes / 4;
+	u8 *val = _val;
+	int i = 0, words = bytes;
 
 	while (words--)
-		writel(*val++, base + reg + (i++ * 4));
+		writeb(*val++, base + reg + i++);
 
 	return 0;
 }
@@ -53,7 +53,7 @@ static int qfprom_remove(struct platform_device *pdev)
 static struct nvmem_config econfig = {
 	.name = "qfprom",
 	.owner = THIS_MODULE,
-	.stride = 4,
+	.stride = 1,
 	.word_size = 1,
 	.reg_read = qfprom_reg_read,
 	.reg_write = qfprom_reg_write,
-- 
The Qualcomm Innovation Center, Inc. is a member of the Code Aurora Forum,
a Linux Foundation Collaborative Project

Re: [PATCH] nvmem: qfprom: Fix to support single byte read/write

[Stephen Boyd]

On 11/15, Vivek Gautam wrote:
> @@ -53,7 +53,7 @@ static int qfprom_remove(struct platform_device *pdev)
>  static struct nvmem_config econfig = {
>  	.name = "qfprom",
>  	.owner = THIS_MODULE,
> -	.stride = 4,
> +	.stride = 1,

Are we certain that all qfproms support byte accesses?

>  	.word_size = 1,
>  	.reg_read = qfprom_reg_read,
>  	.reg_write = qfprom_reg_write,

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Re: [PATCH] nvmem: qfprom: Fix to support single byte read/write

[Vivek Gautam]

Hi Stephen,

On Wed, Nov 16, 2016 at 12:29 AM, Stephen Boyd <sboyd@codeaurora.org> wrote:
> On 11/15, Vivek Gautam wrote:
>> @@ -53,7 +53,7 @@ static int qfprom_remove(struct platform_device *pdev)
>>  static struct nvmem_config econfig = {
>>       .name = "qfprom",
>>       .owner = THIS_MODULE,
>> -     .stride = 4,
>> +     .stride = 1,
>
> Are we certain that all qfproms support byte accesses?

I have tested on 8916 and 8996. Will give a try on older targets as
well.

For a note: we had been using the reg_stride = 1, before removing
regmap support for nvmem access [1].

[1] 382c62f nvmem: qfprom: remove nvmem regmap dependency


Thanks
Vivek

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a Linux Foundation Collaborative Project

Re: [PATCH] nvmem: qfprom: Fix to support single byte read/write

[Stephen Boyd]

On 11/16, Vivek Gautam wrote:
> Hi Stephen,
> 
> On Wed, Nov 16, 2016 at 12:29 AM, Stephen Boyd <sboyd@codeaurora.org> wrote:
> > On 11/15, Vivek Gautam wrote:
> >> @@ -53,7 +53,7 @@ static int qfprom_remove(struct platform_device *pdev)
> >>  static struct nvmem_config econfig = {
> >>       .name = "qfprom",
> >>       .owner = THIS_MODULE,
> >> -     .stride = 4,
> >> +     .stride = 1,
> >
> > Are we certain that all qfproms support byte accesses?
> 
> I have tested on 8916 and 8996. Will give a try on older targets as
> well.
> 
> For a note: we had been using the reg_stride = 1, before removing
> regmap support for nvmem access [1].
> 
> [1] 382c62f nvmem: qfprom: remove nvmem regmap dependency
> 
> 

Ah ok. If we were doing byte accesses before then I have no
concerns.

-- 
Qualcomm Innovation Center, Inc. is a member of Code Aurora Forum,
a Linux Foundation Collaborative Project

[PATCH v2] nvmem: qfprom: Allow single byte accesses for read/write

[Vivek Gautam]

The nvmem core driver supports to read and write single
byte. So, allow qfprom to support this feature.
This change helps in extracting a required value based
on bit-offset and number of bits for the required value
in the nvmem cell.

Signed-off-by: Vivek Gautam <vivek.gautam@codeaurora.org>
Cc: Srinivas Kandagatla <srinivas.kandagatla@linaro.org>
---

Based on torvalds's master branch.
 - Tested on db410c (apq8016) and ifc6410 (apq 8064) targets
   for thermal sensors (could read the core temperatures); and
   on db820c (msm8996) for qusb2 phy, with tree [1] based on
   linaro qcom landing team's integration tree.

Changes in v2:
 - Updated commit title, since the patch does extend the feature,
   rather than fixing any kind of bug in the code.

   Original title (v1): nvmem: qfprom: Fix to support single byte read/write
   Update title (v2): nvmem: qfprom: Allow single byte accesses for read/write.

 - Added some more info in the commit message as well.

 ** NO change in the code.

[1] https://github.com/vivekgautam1/linux/tree/linaro/integration-linux-qcomlt-qcom-phy-upstream

 drivers/nvmem/qfprom.c | 14 +++++++-------
 1 file changed, 7 insertions(+), 7 deletions(-)

diff --git a/drivers/nvmem/qfprom.c b/drivers/nvmem/qfprom.c
index b5305f0..2bdb6c3 100644
--- a/drivers/nvmem/qfprom.c
+++ b/drivers/nvmem/qfprom.c
@@ -21,11 +21,11 @@ static int qfprom_reg_read(void *context,
 			unsigned int reg, void *_val, size_t bytes)
 {
 	void __iomem *base = context;
-	u32 *val = _val;
-	int i = 0, words = bytes / 4;
+	u8 *val = _val;
+	int i = 0, words = bytes;
 
 	while (words--)
-		*val++ = readl(base + reg + (i++ * 4));
+		*val++ = readb(base + reg + i++);
 
 	return 0;
 }
@@ -34,11 +34,11 @@ static int qfprom_reg_write(void *context,
 			 unsigned int reg, void *_val, size_t bytes)
 {
 	void __iomem *base = context;
-	u32 *val = _val;
-	int i = 0, words = bytes / 4;
+	u8 *val = _val;
+	int i = 0, words = bytes;
 
 	while (words--)
-		writel(*val++, base + reg + (i++ * 4));
+		writeb(*val++, base + reg + i++);
 
 	return 0;
 }
@@ -53,7 +53,7 @@ static int qfprom_remove(struct platform_device *pdev)
 static struct nvmem_config econfig = {
 	.name = "qfprom",
 	.owner = THIS_MODULE,
-	.stride = 4,
+	.stride = 1,
 	.word_size = 1,
 	.reg_read = qfprom_reg_read,
 	.reg_write = qfprom_reg_write,
-- 
The Qualcomm Innovation Center, Inc. is a member of the Code Aurora Forum,
a Linux Foundation Collaborative Project

Re: [PATCH v2] nvmem: qfprom: Allow single byte accesses for read/write

[Srinivas Kandagatla]

Thanks for the Patch,

I will queue this up!!

On 17/11/16 05:59, Vivek Gautam wrote:
> The nvmem core driver supports to read and write single
> byte. So, allow qfprom to support this feature.
> This change helps in extracting a required value based
> on bit-offset and number of bits for the required value
> in the nvmem cell.
>
> Signed-off-by: Vivek Gautam <vivek.gautam@codeaurora.org>
> Cc: Srinivas Kandagatla <srinivas.kandagatla@linaro.org>
> ---
>
> Based on torvalds's master branch.
>  - Tested on db410c (apq8016) and ifc6410 (apq 8064) targets
>    for thermal sensors (could read the core temperatures); and
>    on db820c (msm8996) for qusb2 phy, with tree [1] based on
>    linaro qcom landing team's integration tree.
>
> Changes in v2:
>  - Updated commit title, since the patch does extend the feature,
>    rather than fixing any kind of bug in the code.
>
>    Original title (v1): nvmem: qfprom: Fix to support single byte read/write
>    Update title (v2): nvmem: qfprom: Allow single byte accesses for read/write.
>
>  - Added some more info in the commit message as well.
>
>  ** NO change in the code.
>
> [1] https://github.com/vivekgautam1/linux/tree/linaro/integration-linux-qcomlt-qcom-phy-upstream
>
>  drivers/nvmem/qfprom.c | 14 +++++++-------
>  1 file changed, 7 insertions(+), 7 deletions(-)
>
> diff --git a/drivers/nvmem/qfprom.c b/drivers/nvmem/qfprom.c
> index b5305f0..2bdb6c3 100644
> --- a/drivers/nvmem/qfprom.c
> +++ b/drivers/nvmem/qfprom.c
> @@ -21,11 +21,11 @@ static int qfprom_reg_read(void *context,
>  			unsigned int reg, void *_val, size_t bytes)
>  {
>  	void __iomem *base = context;
> -	u32 *val = _val;
> -	int i = 0, words = bytes / 4;
> +	u8 *val = _val;
> +	int i = 0, words = bytes;
>
>  	while (words--)
> -		*val++ = readl(base + reg + (i++ * 4));
> +		*val++ = readb(base + reg + i++);
>
>  	return 0;
>  }
> @@ -34,11 +34,11 @@ static int qfprom_reg_write(void *context,
>  			 unsigned int reg, void *_val, size_t bytes)
>  {
>  	void __iomem *base = context;
> -	u32 *val = _val;
> -	int i = 0, words = bytes / 4;
> +	u8 *val = _val;
> +	int i = 0, words = bytes;
>
>  	while (words--)
> -		writel(*val++, base + reg + (i++ * 4));
> +		writeb(*val++, base + reg + i++);
>
>  	return 0;
>  }
> @@ -53,7 +53,7 @@ static int qfprom_remove(struct platform_device *pdev)
>  static struct nvmem_config econfig = {
>  	.name = "qfprom",
>  	.owner = THIS_MODULE,
> -	.stride = 4,
> +	.stride = 1,
>  	.word_size = 1,
>  	.reg_read = qfprom_reg_read,
>  	.reg_write = qfprom_reg_write,
>

Re: [PATCH v2] nvmem: qfprom: Allow single byte accesses for read/write

[Vivek Gautam]

On Wed, Jan 4, 2017 at 7:37 PM, Srinivas Kandagatla
<srinivas.kandagatla@linaro.org> wrote:
> Thanks for the Patch,
>
> I will queue this up!!

Thanks Srinivas.
[snip]



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