[PATCH v2 2/4] i2c: omap24xx_i2c: Use new function __omap24_i2c_xfer_msg()

[Heiko Schocher]

Hello Aniket,

On 10.03.25 11:36, Aniket Limaye wrote:
> Remove __omap24_i2c_read/write() usage from omap_i2c_xfer() in favour of
> the more flexible __omap24_i2c_xfer_msg().
> Consequently, these are also no longer needed when DM_I2C is enabled.
> 
> New function __omap24_i2c_xfer_msg() will take care of individual read
> OR write transfers with a target device. It goes through below sequence:
> - Program the provided Target Chip address (OMAP_I2C_SA_REG)
> - Program the provided Data len (OMAP_I2C_CNT_REG)
> - Program the provided Control register flags (OMAP_I2C_CON_REG)
> - Read from or Write to the provided Data buffer (OMAP_I2C_DATA_REG)
> 
> For a detailed programming guide, refer to the TRM[0] (12.1.3.4 I2C
> Programming Guide).
> 
> This patch by itself should be a transparent change. However this is
> needed for implementing a proper Repeated Start (Sr) functionality for
> i2c_msgs.
> 
> Previous implementation for omap_i2c_xfer called __omap24_i2c_read/write
> functions, with hardcoded addr=0 and alen=0 for each i2c_msg. Each of
> these calls would program the registers always with a Stop bit set, not
> allowing for a repeated start between i2c_msgs in the same xfer().
> 
> [0]: https://www.ti.com/lit/zip/spruj28 (TRM)
> 
> Signed-off-by: Aniket Limaye <a-limaye at ti.com>
> ---
> 
> v2:
> - Use proper error codes in __omap24_i2c_xfer_msg()
> - Use proper error prints to indicate omap24xx i2c driver
> - Link to v1: https://lore.kernel.org/u-boot/20250304220546.866602-2-a-limaye@ti.com/
> 
> ---
>   drivers/i2c/omap24xx_i2c.c | 143 +++++++++++++++++++++++++++++++------
>   1 file changed, 123 insertions(+), 20 deletions(-)

Thanks!

Reviewed-by: Heiko Schocher <hs at denx.de>

bye,
Heiko

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