Re: [PATCH] usb: typec: tps6598x: handle block writes separately with plain-I2C adapters

From: Nikolaus Voss
Date: Wed Feb 20 2019 - 07:56:49 EST


On Wed, 20 Feb 2019, Heikki Krogerus wrote:

On Mon, Sep 10, 2018 at 07:05:01AM +0200, Nikolaus Voss wrote:
Commit 1a2f474d328f handles block _reads_ separately with plain-I2C
adapters, but the problem described with regmap-i2c not handling
SMBus block transfers (i.e. read and writes) correctly also exists
with writes.

As workaround, this patch adds a block write function the same way
1a2f474d328f adds a block read function.

Fixes: 1a2f474d328f ("usb: typec: tps6598x: handle block reads separately with plain-I2C adapters")
Fixes: 0a4c005bd171 ("usb: typec: driver for TI TPS6598x USB Power Delivery controllers")
Signed-off-by: Nikolaus Voss <nikolaus.voss@xxxxxxxxxxxxxxxxxxxxx>
drivers/usb/typec/tps6598x.c | 22 ++++++++++++++++++----
1 file changed, 18 insertions(+), 4 deletions(-)

diff --git a/drivers/usb/typec/tps6598x.c b/drivers/usb/typec/tps6598x.c
index c84c8c189e90..57a3e6c5c175 100644
--- a/drivers/usb/typec/tps6598x.c
+++ b/drivers/usb/typec/tps6598x.c
@@ -110,6 +110,20 @@ tps6598x_block_read(struct tps6598x *tps, u8 reg, void *val, size_t len)
return 0;

+static int tps6598x_block_write(struct tps6598x *tps, u8 reg,
+ void *val, size_t len)
+ u8 data[len + 1];
+ if (!tps->i2c_protocol)
+ return regmap_raw_write(tps->regmap, reg, val, len);
+ data[0] = len;
+ memcpy(&data[1], val, len);
+ return regmap_raw_write(tps->regmap, reg, data, sizeof(data));
static inline int tps6598x_read16(struct tps6598x *tps, u8 reg, u16 *val)
return tps6598x_block_read(tps, reg, val, sizeof(u16));
@@ -127,23 +141,23 @@ static inline int tps6598x_read64(struct tps6598x *tps, u8 reg, u64 *val)

static inline int tps6598x_write16(struct tps6598x *tps, u8 reg, u16 val)
- return regmap_raw_write(tps->regmap, reg, &val, sizeof(u16));
+ return tps6598x_block_write(tps, reg, &val, sizeof(u16));

static inline int tps6598x_write32(struct tps6598x *tps, u8 reg, u32 val)
- return regmap_raw_write(tps->regmap, reg, &val, sizeof(u32));
+ return tps6598x_block_write(tps, reg, &val, sizeof(u32));

static inline int tps6598x_write64(struct tps6598x *tps, u8 reg, u64 val)
- return regmap_raw_write(tps->regmap, reg, &val, sizeof(u64));
+ return tps6598x_block_write(tps, reg, &val, sizeof(u64));

static inline int
tps6598x_write_4cc(struct tps6598x *tps, u8 reg, const char *val)
- return regmap_raw_write(tps->regmap, reg, &val, sizeof(u32));
+ return tps6598x_block_write(tps, reg, &val, sizeof(u32));

static int tps6598x_read_partner_identity(struct tps6598x *tps)

You need to fix tps6598x_exec_cmd() as well.

Right, thanks. I will fix that.

Did you really send this last September? If you did, then the mail has
been stuck somewhere for a long time.

It's been stuck with me, I forgot to send it ;-).