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From: Thomas Chou <thomas@wytron.com.tw>
To: u-boot@lists.denx.de
Subject: [U-Boot] [PATCH] i2c: fix SDA contention in read_byte()
Date: Mon, 12 Jul 2010 13:51:48 +0800	[thread overview]
Message-ID: <4C3AAD74.7090307@wytron.com.tw> (raw)
In-Reply-To: <4C3AA15E.6070203@emk-elektronik.de>

Reinhard Meyer wrote:
> Its even simpler, provided the  hardware can do open collector. Here was 
> my solution for AVR32AP7000:
> 

Then we could add a config for open drain similar to that of linux driver.

# ifndef I2C_SDA
#  ifdef CONFIG_SOFT_I2C_GPIO_SDA_IS_OPEN_DRAIN
#   define I2C_SDA(bit) gpio_set_value(CONFIG_SOFT_I2C_GPIO_SDA, bit)
#  else
#   define I2C_SDA(bit) \
     if (bit) {                        \
         gpio_direction_input(CONFIG_SOFT_I2C_GPIO_SDA);    \
     } else {                        \
         gpio_direction_output(CONFIG_SOFT_I2C_GPIO_SDA, 0);\
     }
#  endif
# endif

BTW, will you be interested in using common gpio framework for avr32 family?

Cheers,
Thomas

  reply	other threads:[~2010-07-12  5:51 UTC|newest]

Thread overview: 13+ messages / expand[flat|nested]  mbox.gz  Atom feed  top
2010-07-06  6:14 [U-Boot] [PATCH] i2c: fix SDA contention in read_byte() Thomas Chou
2010-07-07  4:45 ` Andrew Dyer
2010-07-07  5:00   ` Reinhard Meyer
2010-07-12  4:14     ` Thomas Chou
2010-07-12  5:00       ` Reinhard Meyer
2010-07-12  5:51         ` Thomas Chou [this message]
2010-07-12  6:49           ` Reinhard Meyer
2010-07-14  1:29             ` Thomas Chou
2010-07-14  6:31               ` Reinhard Meyer
2010-07-21 17:40       ` Mike Frysinger
2010-07-22  2:47         ` Thomas Chou
2010-07-11 22:55   ` Mike Frysinger
2010-07-12  3:47     ` Andrew Dyer

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