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authorMin Li <min.li.xe@renesas.com>2020-11-05 22:52:08 -0500
committerJakub Kicinski <kuba@kernel.org>2020-11-07 13:10:27 -0800
commite4c6eb68343fb1cfe4bffc6802180e91826f76af (patch)
tree5f8faa70fb880be1390d990aa98cf5015a80d6e2 /drivers/ptp/ptp_idt82p33.c
parente014ae39493f6d527f636260117709c1f81b3d57 (diff)
downloadlinux-e4c6eb68343fb1cfe4bffc6802180e91826f76af.tar.bz2
ptp: idt82p33: use i2c_master_send for bus write
Refactor idt82p33_xfer and use i2c_master_send for write operation. Because some I2C controllers are only working with single-burst write transaction. Signed-off-by: Min Li <min.li.xe@renesas.com> Acked-by: Richard Cochran <richardcochran@gmail.com> Link: https://lore.kernel.org/r/1604634729-24960-2-git-send-email-min.li.xe@renesas.com Signed-off-by: Jakub Kicinski <kuba@kernel.org>
Diffstat (limited to 'drivers/ptp/ptp_idt82p33.c')
-rw-r--r--drivers/ptp/ptp_idt82p33.c47
1 files changed, 36 insertions, 11 deletions
diff --git a/drivers/ptp/ptp_idt82p33.c b/drivers/ptp/ptp_idt82p33.c
index 50af339c934a..223bc11cb8fe 100644
--- a/drivers/ptp/ptp_idt82p33.c
+++ b/drivers/ptp/ptp_idt82p33.c
@@ -78,11 +78,10 @@ static void idt82p33_timespec_to_byte_array(struct timespec64 const *ts,
}
}
-static int idt82p33_xfer(struct idt82p33 *idt82p33,
- unsigned char regaddr,
- unsigned char *buf,
- unsigned int count,
- int write)
+static int idt82p33_xfer_read(struct idt82p33 *idt82p33,
+ unsigned char regaddr,
+ unsigned char *buf,
+ unsigned int count)
{
struct i2c_client *client = idt82p33->client;
struct i2c_msg msg[2];
@@ -94,7 +93,7 @@ static int idt82p33_xfer(struct idt82p33 *idt82p33,
msg[0].buf = &regaddr;
msg[1].addr = client->addr;
- msg[1].flags = write ? 0 : I2C_M_RD;
+ msg[1].flags = I2C_M_RD;
msg[1].len = count;
msg[1].buf = buf;
@@ -110,6 +109,31 @@ static int idt82p33_xfer(struct idt82p33 *idt82p33,
return 0;
}
+static int idt82p33_xfer_write(struct idt82p33 *idt82p33,
+ u8 regaddr,
+ u8 *buf,
+ u16 count)
+{
+ struct i2c_client *client = idt82p33->client;
+ /* we add 1 byte for device register */
+ u8 msg[IDT82P33_MAX_WRITE_COUNT + 1];
+ int err;
+
+ if (count > IDT82P33_MAX_WRITE_COUNT)
+ return -EINVAL;
+
+ msg[0] = regaddr;
+ memcpy(&msg[1], buf, count);
+
+ err = i2c_master_send(client, msg, count + 1);
+ if (err < 0) {
+ dev_err(&client->dev, "i2c_master_send returned %d\n", err);
+ return err;
+ }
+
+ return 0;
+}
+
static int idt82p33_page_offset(struct idt82p33 *idt82p33, unsigned char val)
{
int err;
@@ -117,7 +141,7 @@ static int idt82p33_page_offset(struct idt82p33 *idt82p33, unsigned char val)
if (idt82p33->page_offset == val)
return 0;
- err = idt82p33_xfer(idt82p33, PAGE_ADDR, &val, sizeof(val), 1);
+ err = idt82p33_xfer_write(idt82p33, PAGE_ADDR, &val, sizeof(val));
if (err)
dev_err(&idt82p33->client->dev,
"failed to set page offset %d\n", val);
@@ -138,11 +162,12 @@ static int idt82p33_rdwr(struct idt82p33 *idt82p33, unsigned int regaddr,
err = idt82p33_page_offset(idt82p33, page);
if (err)
- goto out;
+ return err;
- err = idt82p33_xfer(idt82p33, offset, buf, count, write);
-out:
- return err;
+ if (write)
+ return idt82p33_xfer_write(idt82p33, offset, buf, count);
+
+ return idt82p33_xfer_read(idt82p33, offset, buf, count);
}
static int idt82p33_read(struct idt82p33 *idt82p33, unsigned int regaddr,