Thread (25 messages) 25 messages, 4 authors, 2017-01-13

Re: [PATCH v8 2/5] i2c: Add STM32F4 I2C driver

From: Uwe Kleine-König <hidden>
Date: 2017-01-13 07:27:30
Also in: linux-arm-kernel, linux-i2c, lkml

Hello,

On Thu, Jan 12, 2017 at 10:28:20PM +0100, M'boumba Cedric Madianga wrote:
Please see below a quote from datasheet that clearly described how to handle
For 2-byte reception:
● Wait until ADDR = 1 (SCL stretched low until the ADDR flag is cleared)
● Set ACK low, set POS high
● Clear ADDR flag
● Wait until BTF = 1 (Data 1 in DR, Data2 in shift register, SCL
stretched low until a data1 is read)
● Set STOP high
● Read data 1 and 2
The problem is that you only know that you have a 2 byte transfer after
you read the first byte (and it's a 1). (But note that this is
irrelevant for the patch as the driver doesn't claim to support this
kind of transfer.)

Best regards
Uwe

-- 
Pengutronix e.K.                           | Uwe Kleine-König            |
Industrial Linux Solutions                 | http://www.pengutronix.de/  |
Keyboard shortcuts
hback out one level
jnext message in thread
kprevious message in thread
ldrill in
Escclose help / fold thread tree
?toggle this help