[PATCH] ARM: ux500: resurrect I2C platform data

[PATCH] ARM: ux500: resurrect I2C platform data

[Linus Walleij]

From: Linus Walleij <linus.walleij@linaro.org>

Commit:
98582d9562b4bea6b0eb6e2bfafcd3fab3b60ccb
"ARM: ux500: Remove unused i2c platform_data initialisation code"

Deleted platform data intialization code that was used,
not unused as indicated in the commit. The boot log (without
devicetree) now looks like this:

nmk-i2c nmk-i2c.0: no platform data
nmk-i2c nmk-i2c.1: no platform data
nmk-i2c nmk-i2c.2: no platform data
nmk-i2c nmk-i2c.3: no platform data

And no I2C drivers register anymore.

Take this opportunity to bump the i2c bus speed to 400kHz.
Some recent discussion revealed inconsistency in the board file
for the MOP500 family. The board can very well do 400kHz on
the I2C busses, so make it do that.

Cc: Srinidhi Kasagar <srinidhi.kasagar@stericsson.com>
Cc: Lee Jones <lee.jones@linaro.org>
Signed-off-by: Linus Walleij <linus.walleij@linaro.org>
---
 arch/arm/mach-ux500/board-mop500.c | 39 ++++++++++++++++++++++++++++++++++----
 1 file changed, 35 insertions(+), 4 deletions(-)

diff --git a/arch/arm/mach-ux500/board-mop500.c b/arch/arm/mach-ux500/board-mop500.c
index 8674a89..dbb9946 100644
--- a/arch/arm/mach-ux500/board-mop500.c
+++ b/arch/arm/mach-ux500/board-mop500.c
@@ -327,12 +327,43 @@ static struct i2c_board_info __initdata mop500_i2c2_devices[] = {
 	},
 };
 
+#define U8500_I2C_CONTROLLER(id, _slsu, _tft, _rft, clk, t_out, _sm)	\
+static struct nmk_i2c_controller u8500_i2c##id##_data = { \
+	/*				\
+	 * slave data setup time, which is	\
+	 * 250 ns,100ns,10ns which is 14,6,2	\
+	 * respectively for a 48 Mhz	\
+	 * i2c clock			\
+	 */				\
+	.slsu		= _slsu,	\
+	/* Tx FIFO threshold */		\
+	.tft		= _tft,		\
+	/* Rx FIFO threshold */		\
+	.rft		= _rft,		\
+	/* std. mode operation */	\
+	.clk_freq	= clk,		\
+	/* Slave response timeout(ms) */\
+	.timeout	= t_out,	\
+	.sm		= _sm,		\
+}
+
+/*
+ * The board uses 4 i2c controllers, initialize all of
+ * them with slave data setup time of 250 ns,
+ * Tx & Rx FIFO threshold values as 1 resp. 8 and fast
+ * mode of operation
+ */
+U8500_I2C_CONTROLLER(0, 0xe, 1, 8, 400000, 200, I2C_FREQ_MODE_FAST);
+U8500_I2C_CONTROLLER(1, 0xe, 1, 8, 400000, 200, I2C_FREQ_MODE_FAST);
+U8500_I2C_CONTROLLER(2,	0xe, 1, 8, 400000, 200, I2C_FREQ_MODE_FAST);
+U8500_I2C_CONTROLLER(3,	0xe, 1, 8, 400000, 200, I2C_FREQ_MODE_FAST);
+
 static void __init mop500_i2c_init(struct device *parent)
 {
-	db8500_add_i2c0(parent, NULL);
-	db8500_add_i2c1(parent, NULL);
-	db8500_add_i2c2(parent, NULL);
-	db8500_add_i2c3(parent, NULL);
+	db8500_add_i2c0(parent, &u8500_i2c0_data);
+	db8500_add_i2c1(parent, &u8500_i2c1_data);
+	db8500_add_i2c2(parent, &u8500_i2c2_data);
+	db8500_add_i2c3(parent, &u8500_i2c3_data);
 }
 
 static struct gpio_keys_button mop500_gpio_keys[] = {
-- 
1.7.11.3

[PATCH] ARM: ux500: resurrect I2C platform data

[Lee Jones]

On Mon, Aug 06, 2012 at 10:52:26AM +0200, Linus Walleij wrote:
> Commit:
> 98582d9562b4bea6b0eb6e2bfafcd3fab3b60ccb
> "ARM: ux500: Remove unused i2c platform_data initialisation code"
> 
> Deleted platform data intialization code that was used,
> not unused as indicated in the commit. The boot log (without
> devicetree) now looks like this:

The aforementioned commit was part of a patch-set. One of its affiliates
moved this code into the Nomadik I2C driver; however, it was contested
because Device Tree support was also added and the maintainer thought 
the properties introduced could be consolidated with other I2C driver's
DT properties. I don't think anyone has taken up the consolidation work
and for that reason it hasn't gone in.

I think moving this stuff into the driver is the right thing to do.
Instead, I'll split out the configuration and DT enablement from the
patch and resubmit.

Sound good to you? 

-- 
Lee Jones
Linaro ST-Ericsson Landing Team Lead
Linaro.org ? Open source software for ARM SoCs
Follow Linaro: Facebook | Twitter | Blog

[PATCH] ARM: ux500: resurrect I2C platform data

[Linus Walleij]

On 08/06/2012 11:51 AM, Lee Jones wrote:
> On Mon, Aug 06, 2012 at 10:52:26AM +0200, Linus Walleij wrote:
>> Commit:
>> 98582d9562b4bea6b0eb6e2bfafcd3fab3b60ccb
>> "ARM: ux500: Remove unused i2c platform_data initialisation code"
>>
>> Deleted platform data intialization code that was used,
>> not unused as indicated in the commit. The boot log (without
>> devicetree) now looks like this:
> The aforementioned commit was part of a patch-set. One of its affiliates
> moved this code into the Nomadik I2C driver; however, it was contested
> because Device Tree support was also added and the maintainer thought
> the properties introduced could be consolidated with other I2C driver's
> DT properties. I don't think anyone has taken up the consolidation work
> and for that reason it hasn't gone in.

Too bad it had to turn into a regression though :-P

> I think moving this stuff into the driver is the right thing to do.
> Instead, I'll split out the configuration and DT enablement from the
> patch and resubmit.
>
> Sound good to you?

Either way works with me, but the patch sent out need to be
rebased and sent to Wolfram. Either he applies that to the I2C
tree or I apply this to the ux500 tree. So it's for Wolfram to decide.

Yours,
Linus Walleij

[PATCH 1/1] i2c: Add default configuration into the Nomadik I2C driver

[Lee Jones]

From: Lee Jones <lee.jones@linaro.org>
Date: Mon, 6 Aug 2012 11:04:14 +0100
Subject: [PATCH 1/1] i2c: Add default configuration into the Nomadik I2C
 driver.

At this moment in time there is only one known configuration for the
Nomadik I2C driver. By not holding that configuration in the driver
adds some unnecessary overhead in platform code. The configuration
as already been removed from platform code, this patch checks for any
over-riding configurations. If there aren't any, the default is used.

Cc: linux-i2c at vger.kernel.org
Signed-off-by: Lee Jones <lee.jones@linaro.org>
---
 drivers/i2c/busses/i2c-nomadik.c |   24 ++++++++++++++++++------
 1 file changed, 18 insertions(+), 6 deletions(-)

diff --git a/drivers/i2c/busses/i2c-nomadik.c b/drivers/i2c/busses/i2c-nomadik.c
index a92440d..86aa73d 100644
--- a/drivers/i2c/busses/i2c-nomadik.c
+++ b/drivers/i2c/busses/i2c-nomadik.c
@@ -333,10 +333,6 @@ static void setup_i2c_controller(struct nmk_i2c_dev *dev)
 
 	i2c_clk = clk_get_rate(dev->clk);
 
-	/* fallback to std. mode if machine has not provided it */
-	if (dev->cfg.clk_freq == 0)
-		dev->cfg.clk_freq = 100000;
-
 	/*
 	 * The spec says, in case of std. mode the divider is
 	 * 2 whereas it is 3 for fast and fastplus mode of
@@ -899,15 +895,31 @@ static const struct i2c_algorithm nmk_i2c_algo = {
 	.functionality	= nmk_i2c_functionality
 };
 
+static struct nmk_i2c_controller u8500_i2c = {
+	/*
+	 * Slave data setup time; 250ns, 100ns, and 10ns, which
+	 * is 14, 6 and 2 respectively for a 48Mhz i2c clock.
+	 */
+	.slsu           = 0xe,
+	.tft            = 1,      /* Tx FIFO threshold */
+	.rft            = 8,      /* Rx FIFO threshold */
+	.clk_freq       = 400000, /* std. mode operation */
+	.timeout        = 200,    /* Slave response timeout(ms) */
+	.sm             = I2C_FREQ_MODE_FAST,
+};
+
 static int __devinit nmk_i2c_probe(struct platform_device *pdev)
 {
 	int ret = 0;
 	struct resource *res;
-	struct nmk_i2c_controller *pdata =
-			pdev->dev.platform_data;
+	struct nmk_i2c_controller *pdata = pdev->dev.platform_data;
 	struct nmk_i2c_dev	*dev;
 	struct i2c_adapter *adap;
 
+	if (!pdata)
+		/* No i2c configuration found, using the default. */
+		pdata = &u8500_i2c;
+
 	dev = kzalloc(sizeof(struct nmk_i2c_dev), GFP_KERNEL);
 	if (!dev) {
 		dev_err(&pdev->dev, "cannot allocate memory\n");
-- 
1.7.9.5

[PATCH 1/1] i2c: Add default configuration into the Nomadik I2C driver

[Linus Walleij]

On Mon, Aug 6, 2012 at 12:21 PM, Lee Jones <lee.jones@linaro.org> wrote:

> From: Lee Jones <lee.jones@linaro.org>
> Date: Mon, 6 Aug 2012 11:04:14 +0100
> Subject: [PATCH 1/1] i2c: Add default configuration into the Nomadik I2C
>  driver.
>
> At this moment in time there is only one known configuration for the
> Nomadik I2C driver. By not holding that configuration in the driver
> adds some unnecessary overhead in platform code. The configuration
> as already been removed from platform code, this patch checks for any
> over-riding configurations. If there aren't any, the default is used.
>
> Cc: linux-i2c at vger.kernel.org
> Signed-off-by: Lee Jones <lee.jones@linaro.org>

Ah, I created my own solution for this as well by reverting back
some platform data.

This works too, but the patch does not apply to v3.6-rc1.
Please rebase and repost, then you can add my
Acked-by: Linus Walleij <linus.walleij@linaro.org>

Please not that you need to send I2C patches for embedded
to Wolfram Sang.

Wolfram, please pick this for the -rc series because it's a regression
in v3.6-rc1.

Yours,
Linus Walleij

[PATCH 1/1] i2c: Add default configuration into the Nomadik I2C driver

[Srinidhi Kasagar]

On Mon, Aug 06, 2012 at 12:21:52 +0200, Lee Jones wrote:
> From: Lee Jones <lee.jones@linaro.org>
> Date: Mon, 6 Aug 2012 11:04:14 +0100
> Subject: [PATCH 1/1] i2c: Add default configuration into the Nomadik I2C
>  driver.
> 
> At this moment in time there is only one known configuration for the
> Nomadik I2C driver. By not holding that configuration in the driver
> adds some unnecessary overhead in platform code. The configuration
> as already been removed from platform code, this patch checks for any
> over-riding configurations. If there aren't any, the default is used.
> 
> Cc: linux-i2c at vger.kernel.org
> Signed-off-by: Lee Jones <lee.jones@linaro.org>
> ---
>  drivers/i2c/busses/i2c-nomadik.c |   24 ++++++++++++++++++------
>  1 file changed, 18 insertions(+), 6 deletions(-)
> 
> diff --git a/drivers/i2c/busses/i2c-nomadik.c b/drivers/i2c/busses/i2c-nomadik.c
> index a92440d..86aa73d 100644
> --- a/drivers/i2c/busses/i2c-nomadik.c
> +++ b/drivers/i2c/busses/i2c-nomadik.c
> @@ -333,10 +333,6 @@ static void setup_i2c_controller(struct nmk_i2c_dev *dev)
>  
>  	i2c_clk = clk_get_rate(dev->clk);
>  
> -	/* fallback to std. mode if machine has not provided it */
> -	if (dev->cfg.clk_freq == 0)
> -		dev->cfg.clk_freq = 100000;
> -
>  	/*
>  	 * The spec says, in case of std. mode the divider is
>  	 * 2 whereas it is 3 for fast and fastplus mode of
> @@ -899,15 +895,31 @@ static const struct i2c_algorithm nmk_i2c_algo = {
>  	.functionality	= nmk_i2c_functionality
>  };
>  
> +static struct nmk_i2c_controller u8500_i2c = {
> +	/*
> +	 * Slave data setup time; 250ns, 100ns, and 10ns, which
> +	 * is 14, 6 and 2 respectively for a 48Mhz i2c clock.
> +	 */
> +	.slsu           = 0xe,
> +	.tft            = 1,      /* Tx FIFO threshold */
> +	.rft            = 8,      /* Rx FIFO threshold */
> +	.clk_freq       = 400000, /* std. mode operation */
"Fast mode operation" in comment, or use your favorite "upto" keyword.

Otherwise it is Acked-by: srinidhi kasagar <srinidhi.kasagar@stericsson.com>

/srinidhi