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

lists.openwall.net		lists / announce owl-users owl-dev john-users john-dev passwdqc-users yescrypt popa3d-users / oss-security kernel-hardening musl sabotage tlsify passwords / crypt-dev xvendor / Bugtraq Full-Disclosure linux-kernel linux-netdev linux-ext4 linux-hardening linux-cve-announce PHC
Open Source and information security mailing list archives

Hash Suite: Windows password security audit tool. GUI, reports in PDF.

[<prev] [next>] [<thread-prev] [thread-next>] [day] [month] [year] [list]

Date:   Thu, 17 Nov 2016 11:29:05 +0530
From:   Vivek Gautam <vivek.gautam@...eaurora.org>
To:     srinivas.kandagatla@...aro.org
Cc:     maxime.ripard@...e-electrons.com, gregkh@...uxfoundation.org,
        sboyd@...eaurora.org, rnayak@...eaurora.org,
        linux-kernel@...r.kernel.org, linux-arm-msm@...r.kernel.org,
        Vivek Gautam <vivek.gautam@...eaurora.org>
Subject: [PATCH v2] nvmem: qfprom: Allow single byte accesses for read/write

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@...eaurora.org>
Cc: Srinivas Kandagatla <srinivas.kandagatla@...aro.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