From mboxrd@z Thu Jan 1 00:00:00 1970 From: Heiko Schocher Date: Mon, 20 Jul 2009 09:40:43 +0200 Subject: [U-Boot] [PATCH 0/2] arm nomadik: gpio and i2c In-Reply-To: References: Message-ID: <4A641F7B.1000508@denx.de> List-Id: MIME-Version: 1.0 Content-Type: text/plain; charset="us-ascii" Content-Transfer-Encoding: 7bit To: u-boot@lists.denx.de Hello Alessandro, Alessandro Rubini wrote: > This adds gpio and i2c support for the Nomadik evaluation kit. They > are needed to turn on the LCD backlight in order to later add LCD > support. > > I have one doubt and some questions on gpio: > > To use soft_i2c I need to define some macros in the config file. > Instead of writing hard numbers there I called the gpio functions, but > the config file is inluded from asm sources as well. I don't think my > approach is beautiful at all (both #ifndef __ASSEMBLY__ and #include > "../board/"), but I didn't find a better solution. Yes, thats a problem ... if we had a GPIO Framework it would be solved by including gpio.h ... Or, maybe, we can make a soft_i2c.h which which gets only included if saying CONFIG_I2C_SOFT_INCLUDE is defined. soft_i2c.h defines for example: #define I2C_SDA(x) i2c_soft_sda(bit) void i2c_soft_sda(int pin); and you can define this function i2c_soft_sda(int pin) in your board specific code ... maybe a cleaner option? to speak in c, I tried the following patch on the suen3 plattform, where I have actually a similiar problem, and this worked fine :-) [PATCH] i2c, soft: added soft_i2c.h In case you must define functions for the I2C_XXX defines, it is necessary to have a soft_i2c.h, which defines functions for this macros. This functions can then be programmed in board specific code. To activate this it must be CONFIG_I2C_SOFT_INCLUDE defined in the board config file. Signed-off-by: Heiko Schocher --- drivers/i2c/soft_i2c.c | 3 +++ include/soft_i2c.h | 16 ++++++++++++++++ 2 files changed, 19 insertions(+), 0 deletions(-) create mode 100644 include/soft_i2c.h diff --git a/drivers/i2c/soft_i2c.c b/drivers/i2c/soft_i2c.c index 59883a5..30e24f3 100644 --- a/drivers/i2c/soft_i2c.c +++ b/drivers/i2c/soft_i2c.c @@ -43,6 +43,9 @@ #if defined(CONFIG_MPC852T) || defined(CONFIG_MPC866) #include #endif +#if defined(CONFIG_SOFT_I2C_INCLUDE) +#include +#endif #include /* #define DEBUG_I2C */ diff --git a/include/soft_i2c.h b/include/soft_i2c.h new file mode 100644 index 0000000..39f9a35 --- /dev/null +++ b/include/soft_i2c.h @@ -0,0 +1,16 @@ +#ifndef _CONFIG_SOFT_I2C +#define _CONFIG_SOFT_I2C +#define I2C_ACTIVE i2c_soft_active(); +#define I2C_TRISTATE i2c_soft_tristate(); +#define I2C_READ i2c_soft_read(); +#define I2C_SDA(bit) i2c_soft_sda(bit); +#define I2C_SCL(bit) i2c_soft_scl(bit); +#define I2C_DELAY i2c_soft_delay(); + +void i2c_soft_active(void); +void i2c_soft_tristate(void); +int i2c_soft_read(void); +void i2c_soft_sda(int value); +void i2c_soft_scl(int value); +void i2c_soft_delay(void); +#endif -- 1.6.0.GIT Maybe you can try it too? > I would like to add a gpio command, and I've found no generic gpio > stuff. Only one board (cm-bf527) has a gpio commands, but quite a few > have similar commands to set leds or other bits. Is time ripe for a > generic gpio driver with board-specific limits and operations? Would > that be interesting for u-boot-next? Should I process with a board-specific > gpio command by now? I vote for making a gpio framework, but that will take a while I think ... Hmm.. maybe we use my proposal for such a soft_i2c.h, so I think, it is okay for such a board specific gpio (unless we have a gpio framework). bye Heiko -- DENX Software Engineering GmbH, MD: Wolfgang Denk & Detlev Zundel HRB 165235 Munich, Office: Kirchenstr.5, D-82194 Groebenzell, Germany