Hi Dmitry

On 2019/08/17 2:18, Dmitry Torokhov wrote:

On Fri, Aug 16, 2019 at 05:28:53PM +0900, Jiada Wang wrote:

quoted

From: Nick Dyer <redacted>

On some firmware variants, the size of the info block exceeds what can
be read in a single transfer.

Signed-off-by: Nick Dyer <redacted>
(cherry picked from ndyer/linux/for-upstream commit 74c4f5277cfa403d43fafc404119dc57a08677db)
[gdavis: Forward port and fix conflicts due to v4.14.51 commit
	 960fe000b1d3 ("Input: atmel_mxt_ts - fix the firmware
	 update").]
Signed-off-by: George G. Davis <redacted>
Signed-off-by: Jiada Wang <redacted>
---
  drivers/input/touchscreen/atmel_mxt_ts.c | 27 +++++++++++++++++++++---
  1 file changed, 24 insertions(+), 3 deletions(-)

diff --git a/drivers/input/touchscreen/atmel_mxt_ts.c b/drivers/input/touchscreen/atmel_mxt_ts.c
index 9b165d23e092..2d70ddf71cd9 100644
--- a/drivers/input/touchscreen/atmel_mxt_ts.c
+++ b/drivers/input/touchscreen/atmel_mxt_ts.c

@@ -40,7 +40,7 @@
  #define MXT_OBJECT_START	0x07
  #define MXT_OBJECT_SIZE		6
  #define MXT_INFO_CHECKSUM_SIZE	3
-#define MXT_MAX_BLOCK_WRITE	256
+#define MXT_MAX_BLOCK_WRITE	255
  
  /* Object types */
  #define MXT_DEBUG_DIAGNOSTIC_T37	37

@@ -659,6 +659,27 @@ static int __mxt_read_reg(struct i2c_client *client,
  	return ret;
  }
  
+static int mxt_read_blks(struct mxt_data *data, u16 start, u16 count, u8 *buf)

Can we call this __mxt_read_reg() and the original read reg call
__mxt_read_chunk()?

yes, I will update in v2 patch-set,
so that every call to __mxt_read_reg() in atmel driver,
can have the feature to split large size transfer.

Thanks,
Jiada

quoted

+{
+	u16 offset = 0;
+	int error;
+	u16 size;
+
+	while (offset < count) {
+		size = min(MXT_MAX_BLOCK_WRITE, count - offset);
+
+		error = __mxt_read_reg(data->client,
+				       start + offset,
+				       size, buf + offset);
+		if (error)
+			return error;
+
+		offset += size;
+	}
+
+	return 0;
+}

Thanks.