[PATCH 0/3] introduce stmp-style devices

[PATCH 0/3] introduce stmp-style devices

[Wolfram Sang]

This series makes support for a certain type of devices mach independant. We
want that because such devices (having a special register layout) have been
found in mach-mxs and mach-mx6 meanwhile. Please refer to patch 1/3 for a more
detailed description.

Patch 1/3 adds the basic support and is of main interest to get upstream.
Patches 2/3 and 3/3 are usage examples and will be send to the relevant
subsystems once the basic support is accepted.

Main changes since the RFC:

* renamed the macros to STMP_OFFSET_*
* rebased to 3.3-rc6

Tested with a TX28 board.

Thanks,

   Wolfram

Wolfram Sang (3):
  drivers: base: add support for stmp-style devices
  i2c: mxs: use global reset function
  rtc: stmp3xxx: use global stmp_device functionality

 drivers/base/Kconfig         |    3 ++
 drivers/base/Makefile        |    1 +
 drivers/base/stmp_device.c   |   80 ++++++++++++++++++++++++++++++++++++++++++
 drivers/i2c/busses/Kconfig   |    1 +
 drivers/i2c/busses/i2c-mxs.c |    9 +----
 drivers/rtc/Kconfig          |    1 +
 drivers/rtc/rtc-stmp3xxx.c   |   29 +++++----------
 include/linux/stmp_device.h  |   19 ++++++++++
 8 files changed, 117 insertions(+), 26 deletions(-)
 create mode 100644 drivers/base/stmp_device.c
 create mode 100644 include/linux/stmp_device.h

-- 
1.7.9.1

[PATCH 1/3] drivers: base: add support for stmp-style devices

[Wolfram Sang]

MX23/28 use IP cores which follow a register layout I have first seen on
STMP3xxx SoCs. In this layout, every register actually has four u32:

 1.) to store a value directly
 2.) a SET register where every 1-bit sets the corresponding bit,
     others are unaffected
 3.) same with a CLR register
 4.) same with a TOG (toggle) register

Also, the 2 MSBs in register 0 are always the same and can be used to reset
the IP core.

All this is strictly speaking not mach-specific (but IP core specific) and,
thus, doesn't need to be in mach-mxs/include. At least mx6 also uses IP cores
following this stmp-style. So:

Introduce a stmp-style device, put the code and defines for that in a public
place (drivers/base/), and let drivers for stmp-style devices select that code.
To avoid regressions and ease reviewing, the actual code is simply copied from
mach-mxs. It definately wants updates, but those need a seperate patch series.

Voila, mach dependency gone, reusable code introduced. Note that I didn't
remove the duplicated code from mach-mxs yet, first the drivers have to be
converted.

Signed-off-by: Wolfram Sang <w.sang@pengutronix.de>
---
 drivers/base/Kconfig        |    3 ++
 drivers/base/Makefile       |    1 +
 drivers/base/stmp_device.c  |   80 +++++++++++++++++++++++++++++++++++++++++++
 include/linux/stmp_device.h |   19 ++++++++++
 4 files changed, 103 insertions(+), 0 deletions(-)
 create mode 100644 drivers/base/stmp_device.c
 create mode 100644 include/linux/stmp_device.h

diff --git a/drivers/base/Kconfig b/drivers/base/Kconfig
index 7be9f79..bcd3356 100644
--- a/drivers/base/Kconfig
+++ b/drivers/base/Kconfig
@@ -176,6 +176,9 @@ config GENERIC_CPU_DEVICES
 	bool
 	default n
 
+config STMP_DEVICE
+	bool
+
 source "drivers/base/regmap/Kconfig"
 
 config DMA_SHARED_BUFFER
diff --git a/drivers/base/Makefile b/drivers/base/Makefile
index 610f999..86e4134 100644
--- a/drivers/base/Makefile
+++ b/drivers/base/Makefile
@@ -18,6 +18,7 @@ ifeq ($(CONFIG_SYSFS),y)
 obj-$(CONFIG_MODULES)	+= module.o
 endif
 obj-$(CONFIG_SYS_HYPERVISOR) += hypervisor.o
+obj-$(CONFIG_STMP_DEVICE) += stmp_device.o
 obj-$(CONFIG_REGMAP)	+= regmap/
 
 ccflags-$(CONFIG_DEBUG_DRIVER) := -DDEBUG
diff --git a/drivers/base/stmp_device.c b/drivers/base/stmp_device.c
new file mode 100644
index 0000000..8ac9bcc
--- /dev/null
+++ b/drivers/base/stmp_device.c
@@ -0,0 +1,80 @@
+/*
+ * Copyright (C) 1999 ARM Limited
+ * Copyright (C) 2000 Deep Blue Solutions Ltd
+ * Copyright 2006-2007,2010 Freescale Semiconductor, Inc. All Rights Reserved.
+ * Copyright 2008 Juergen Beisert, kernel at pengutronix.de
+ * Copyright 2009 Ilya Yanok, Emcraft Systems Ltd, yanok at emcraft.com
+ * Copyright (C) 2011 Wolfram Sang, Pengutronix e.K.
+ *
+ * This program is free software; you can redistribute it and/or modify
+ * it under the terms of the GNU General Public License as published by
+ * the Free Software Foundation; either version 2 of the License, or
+ * (at your option) any later version.
+ */
+
+#include <linux/io.h>
+#include <linux/errno.h>
+#include <linux/delay.h>
+#include <linux/module.h>
+#include <linux/stmp_device.h>
+
+#define STMP_MODULE_CLKGATE	(1 << 30)
+#define STMP_MODULE_SFTRST	(1 << 31)
+
+/*
+ * Clear the bit and poll it cleared.  This is usually called with
+ * a reset address and mask being either SFTRST(bit 31) or CLKGATE
+ * (bit 30).
+ */
+static int stmp_clear_poll_bit(void __iomem *addr, u32 mask)
+{
+	int timeout = 0x400;
+
+	writel(mask, addr + STMP_OFFSET_REG_CLR);
+	udelay(1);
+	while ((readl(addr) & mask) && --timeout)
+		/* nothing */;
+
+	return !timeout;
+}
+
+int stmp_reset_block(void __iomem *reset_addr)
+{
+	int ret;
+	int timeout = 0x400;
+
+	/* clear and poll SFTRST */
+	ret = stmp_clear_poll_bit(reset_addr, STMP_MODULE_SFTRST);
+	if (unlikely(ret))
+		goto error;
+
+	/* clear CLKGATE */
+	writel(STMP_MODULE_CLKGATE, reset_addr + STMP_OFFSET_REG_CLR);
+
+	/* set SFTRST to reset the block */
+	writel(STMP_MODULE_SFTRST, reset_addr + STMP_OFFSET_REG_SET);
+	udelay(1);
+
+	/* poll CLKGATE becoming set */
+	while ((!(readl(reset_addr) & STMP_MODULE_CLKGATE)) && --timeout)
+		/* nothing */;
+	if (unlikely(!timeout))
+		goto error;
+
+	/* clear and poll SFTRST */
+	ret = stmp_clear_poll_bit(reset_addr, STMP_MODULE_SFTRST);
+	if (unlikely(ret))
+		goto error;
+
+	/* clear and poll CLKGATE */
+	ret = stmp_clear_poll_bit(reset_addr, STMP_MODULE_CLKGATE);
+	if (unlikely(ret))
+		goto error;
+
+	return 0;
+
+error:
+	pr_err("%s(%p): module reset timeout\n", __func__, reset_addr);
+	return -ETIMEDOUT;
+}
+EXPORT_SYMBOL(stmp_reset_block);
diff --git a/include/linux/stmp_device.h b/include/linux/stmp_device.h
new file mode 100644
index 0000000..d088de2
--- /dev/null
+++ b/include/linux/stmp_device.h
@@ -0,0 +1,19 @@
+/*
+ * basic functions for devices following the "stmp" style register layout
+ *
+ * Copyright (C) 2011 Wolfram Sang, Pengutronix e.K.
+ *
+ * This program is free software; you can redistribute it and/or modify
+ * it under the terms of the GNU General Public License as published by
+ * the Free Software Foundation; version 2 of the License.
+ */
+
+#ifndef __STMP_DEVICE_H__
+#define __STMP_DEVICE_H__
+
+#define STMP_OFFSET_REG_SET	0x4
+#define STMP_OFFSET_REG_CLR	0x8
+#define STMP_OFFSET_REG_TOG	0xc
+
+extern int stmp_reset_block(void __iomem *);
+#endif /* __STMP_DEVICE_H__ */
-- 
1.7.9.1

[PATCH 1/3] drivers: base: add support for stmp-style devices

[Fabio Estevam]

On Wed, Mar 7, 2012 at 7:28 PM, Wolfram Sang <w.sang@pengutronix.de> wrote:
...
> +static int stmp_clear_poll_bit(void __iomem *addr, u32 mask)
> +{
> + ? ? ? int timeout = 0x400;

Could you please add a proper timeout mechanism here?

Something like: http://patchwork.ozlabs.org/patch/137365/

,as you suggested in the first place ;-)

> +
> + ? ? ? writel(mask, addr + STMP_OFFSET_REG_CLR);
> + ? ? ? udelay(1);
> + ? ? ? while ((readl(addr) & mask) && --timeout)
> + ? ? ? ? ? ? ? /* nothing */;
> +
> + ? ? ? return !timeout;
> +}
> +
> +int stmp_reset_block(void __iomem *reset_addr)
> +{
> + ? ? ? int ret;
> + ? ? ? int timeout = 0x400;

Same here.

Regards,

Fabio Estevam

[PATCH 1/3] drivers: base: add support for stmp-style devices

[Wolfram Sang]

On Wed, Mar 07, 2012 at 07:40:22PM -0300, Fabio Estevam wrote:
> On Wed, Mar 7, 2012 at 7:28 PM, Wolfram Sang <w.sang@pengutronix.de> wrote:
> ...
> > +static int stmp_clear_poll_bit(void __iomem *addr, u32 mask)
> > +{
> > + ? ? ? int timeout = 0x400;
> 
> Could you please add a proper timeout mechanism here?
> 
> Something like: http://patchwork.ozlabs.org/patch/137365/

>From the patch description:

===

To avoid regressions and ease reviewing, the actual code is simply copied from
mach-mxs. It definately wants updates, but those need a seperate patch series.

===

Or is that considered a wrong path?

Thanks,

   Wolfram

-- 
Pengutronix e.K.                           | Wolfram Sang                |
Industrial Linux Solutions                 | http://www.pengutronix.de/  |
-------------- next part --------------
A non-text attachment was scrubbed...
Name: signature.asc
Type: application/pgp-signature
Size: 198 bytes
Desc: Digital signature
URL: <http://lists.infradead.org/pipermail/linux-arm-kernel/attachments/20120308/cb794861/attachment.sig>

[PATCH 1/3] drivers: base: add support for stmp-style devices

[Huang Shijie]

? 2012?03?08? 06:28, Wolfram Sang ??:
> All this is strictly speaking not mach-specific (but IP core specific) and,
> thus, doesn't need to be in mach-mxs/include. At least mx6 also uses IP cores
> following this stmp-style. So:
>
mx50 also uses the same IP core.

BR
Huang Shijie

[PATCH 1/3] drivers: base: add support for stmp-style devices

[Shawn Guo]

On Wed, Mar 07, 2012 at 11:28:32PM +0100, Wolfram Sang wrote:
> MX23/28 use IP cores which follow a register layout I have first seen on
> STMP3xxx SoCs. In this layout, every register actually has four u32:
> 
>  1.) to store a value directly
>  2.) a SET register where every 1-bit sets the corresponding bit,
>      others are unaffected
>  3.) same with a CLR register
>  4.) same with a TOG (toggle) register
> 
> Also, the 2 MSBs in register 0 are always the same and can be used to reset
> the IP core.
> 
> All this is strictly speaking not mach-specific (but IP core specific) and,
> thus, doesn't need to be in mach-mxs/include. At least mx6 also uses IP cores
> following this stmp-style. So:
> 
> Introduce a stmp-style device, put the code and defines for that in a public
> place (drivers/base/), and let drivers for stmp-style devices select that code.
> To avoid regressions and ease reviewing, the actual code is simply copied from
> mach-mxs. It definately wants updates, but those need a seperate patch series.
> 
> Voila, mach dependency gone, reusable code introduced. Note that I didn't
> remove the duplicated code from mach-mxs yet, first the drivers have to be
> converted.
> 
> Signed-off-by: Wolfram Sang <w.sang@pengutronix.de>

Acked-by: Shawn Guo <shawn.guo@linaro.org>

[PATCH 2/3] i2c: mxs: use global reset function

[Wolfram Sang]

The former mach specific reset_block function has been converted to a global
one. Use the new one to remove mach dependency from the driver.

Signed-off-by: Wolfram Sang <w.sang@pengutronix.de>
---
 drivers/i2c/busses/Kconfig   |    1 +
 drivers/i2c/busses/i2c-mxs.c |    9 ++-------
 2 files changed, 3 insertions(+), 7 deletions(-)

diff --git a/drivers/i2c/busses/Kconfig b/drivers/i2c/busses/Kconfig
index 3101dd5..d4378cf 100644
--- a/drivers/i2c/busses/Kconfig
+++ b/drivers/i2c/busses/Kconfig
@@ -467,6 +467,7 @@ config I2C_MV64XXX
 config I2C_MXS
 	tristate "Freescale i.MX28 I2C interface"
 	depends on SOC_IMX28
+	select STMP_DEVICE
 	help
 	  Say Y here if you want to use the I2C bus controller on
 	  the Freescale i.MX28 processors.
diff --git a/drivers/i2c/busses/i2c-mxs.c b/drivers/i2c/busses/i2c-mxs.c
index 3d471d5..0834802 100644
--- a/drivers/i2c/busses/i2c-mxs.c
+++ b/drivers/i2c/busses/i2c-mxs.c
@@ -26,8 +26,7 @@
 #include <linux/platform_device.h>
 #include <linux/jiffies.h>
 #include <linux/io.h>
-
-#include <mach/common.h>
+#include <linux/stmp_device.h>
 
 #define DRIVER_NAME "mxs-i2c"
 
@@ -111,13 +110,9 @@ struct mxs_i2c_dev {
 	struct i2c_adapter adapter;
 };
 
-/*
- * TODO: check if calls to here are really needed. If not, we could get rid of
- * mxs_reset_block and the mach-dependency. Needs an I2C analyzer, probably.
- */
 static void mxs_i2c_reset(struct mxs_i2c_dev *i2c)
 {
-	mxs_reset_block(i2c->regs);
+	stmp_reset_block(i2c->regs);
 	writel(MXS_I2C_IRQ_MASK << 8, i2c->regs + MXS_I2C_CTRL1_SET);
 	writel(MXS_I2C_QUEUECTRL_PIO_QUEUE_MODE,
 			i2c->regs + MXS_I2C_QUEUECTRL_SET);
-- 
1.7.9.1

[PATCH 3/3] rtc: stmp3xxx: use global stmp_device functionality

[Wolfram Sang]

The former mach specific reset_block function has been converted to a global
one. Use the new one to remove mach dependency from the driver. Also simplify
code using the new STMP_OFFSET_REG_* macros.

Signed-off-by: Wolfram Sang <w.sang@pengutronix.de>
---
 drivers/rtc/Kconfig        |    1 +
 drivers/rtc/rtc-stmp3xxx.c |   29 ++++++++++-------------------
 2 files changed, 11 insertions(+), 19 deletions(-)

diff --git a/drivers/rtc/Kconfig b/drivers/rtc/Kconfig
index 3a125b8..e124f93 100644
--- a/drivers/rtc/Kconfig
+++ b/drivers/rtc/Kconfig
@@ -983,6 +983,7 @@ config RTC_DRV_COH901331
 config RTC_DRV_STMP
 	tristate "Freescale STMP3xxx/i.MX23/i.MX28 RTC"
 	depends on ARCH_MXS
+	select STMP_DEVICE
 	help
 	  If you say yes here you will get support for the onboard
 	  STMP3xxx/i.MX23/i.MX28 RTC.
diff --git a/drivers/rtc/rtc-stmp3xxx.c b/drivers/rtc/rtc-stmp3xxx.c
index 1028786..e755d3e 100644
--- a/drivers/rtc/rtc-stmp3xxx.c
+++ b/drivers/rtc/rtc-stmp3xxx.c
@@ -25,11 +25,9 @@
 #include <linux/interrupt.h>
 #include <linux/rtc.h>
 #include <linux/slab.h>
-
-#include <mach/common.h>
+#include <linux/stmp_device.h>
 
 #define STMP3XXX_RTC_CTRL			0x0
-#define STMP3XXX_RTC_CTRL_SET			0x4
 #define STMP3XXX_RTC_CTRL_CLR			0x8
 #define STMP3XXX_RTC_CTRL_ALARM_IRQ_EN		0x00000001
 #define STMP3XXX_RTC_CTRL_ONEMSEC_IRQ_EN	0x00000002
@@ -44,7 +42,6 @@
 #define STMP3XXX_RTC_ALARM			0x40
 
 #define STMP3XXX_RTC_PERSISTENT0		0x60
-#define STMP3XXX_RTC_PERSISTENT0_SET		0x64
 #define STMP3XXX_RTC_PERSISTENT0_CLR		0x68
 #define STMP3XXX_RTC_PERSISTENT0_ALARM_WAKE_EN	0x00000002
 #define STMP3XXX_RTC_PERSISTENT0_ALARM_EN	0x00000004
@@ -106,20 +103,14 @@ static irqreturn_t stmp3xxx_rtc_interrupt(int irq, void *dev_id)
 static int stmp3xxx_alarm_irq_enable(struct device *dev, unsigned int enabled)
 {
 	struct stmp3xxx_rtc_data *rtc_data = dev_get_drvdata(dev);
+	u32 set_clr_offset = enabled ? STMP_OFFSET_REG_SET : STMP_OFFSET_REG_CLR;
+
+	writel(STMP3XXX_RTC_PERSISTENT0_ALARM_EN |
+		STMP3XXX_RTC_PERSISTENT0_ALARM_WAKE_EN,
+		rtc_data->io + STMP3XXX_RTC_PERSISTENT0 + set_clr_offset);
+	writel(STMP3XXX_RTC_CTRL_ALARM_IRQ_EN,
+		rtc_data->io + STMP3XXX_RTC_CTRL + set_clr_offset);
 
-	if (enabled) {
-		writel(STMP3XXX_RTC_PERSISTENT0_ALARM_EN |
-				STMP3XXX_RTC_PERSISTENT0_ALARM_WAKE_EN,
-				rtc_data->io + STMP3XXX_RTC_PERSISTENT0_SET);
-		writel(STMP3XXX_RTC_CTRL_ALARM_IRQ_EN,
-				rtc_data->io + STMP3XXX_RTC_CTRL_SET);
-	} else {
-		writel(STMP3XXX_RTC_PERSISTENT0_ALARM_EN |
-				STMP3XXX_RTC_PERSISTENT0_ALARM_WAKE_EN,
-				rtc_data->io + STMP3XXX_RTC_PERSISTENT0_CLR);
-		writel(STMP3XXX_RTC_CTRL_ALARM_IRQ_EN,
-				rtc_data->io + STMP3XXX_RTC_CTRL_CLR);
-	}
 	return 0;
 }
 
@@ -206,7 +197,7 @@ static int stmp3xxx_rtc_probe(struct platform_device *pdev)
 
 	platform_set_drvdata(pdev, rtc_data);
 
-	mxs_reset_block(rtc_data->io);
+	stmp_reset_block(rtc_data->io);
 	writel(STMP3XXX_RTC_PERSISTENT0_ALARM_EN |
 			STMP3XXX_RTC_PERSISTENT0_ALARM_WAKE_EN |
 			STMP3XXX_RTC_PERSISTENT0_ALARM_WAKE,
@@ -253,7 +244,7 @@ static int stmp3xxx_rtc_resume(struct platform_device *dev)
 {
 	struct stmp3xxx_rtc_data *rtc_data = platform_get_drvdata(dev);
 
-	mxs_reset_block(rtc_data->io);
+	stmp_reset_block(rtc_data->io);
 	writel(STMP3XXX_RTC_PERSISTENT0_ALARM_EN |
 			STMP3XXX_RTC_PERSISTENT0_ALARM_WAKE_EN |
 			STMP3XXX_RTC_PERSISTENT0_ALARM_WAKE,
-- 
1.7.9.1

[PATCH 0/3] introduce stmp-style devices

[Arnd Bergmann]

On Wednesday 07 March 2012, Wolfram Sang wrote:
> 
> This series makes support for a certain type of devices mach independant. We
> want that because such devices (having a special register layout) have been
> found in mach-mxs and mach-mx6 meanwhile. Please refer to patch 1/3 for a more
> detailed description.
> 
> Patch 1/3 adds the basic support and is of main interest to get upstream.
> Patches 2/3 and 3/3 are usage examples and will be send to the relevant
> subsystems once the basic support is accepted.
> 
> Main changes since the RFC:
> 
> * renamed the macros to STMP_OFFSET_*
> * rebased to 3.3-rc6
> 
> Tested with a TX28 board.

I think having the stmp_device code is good, but I'm not sure about the
location in drivers/base, which is otherwise reserved for anything related
to 'struct device'. How about putting the same file into lib/stmpregs.c?

	Arnd

[PATCH 0/3] introduce stmp-style devices

[Wolfram Sang]

> I think having the stmp_device code is good, but I'm not sure about the
> location in drivers/base, which is otherwise reserved for anything related
> to 'struct device'. How about putting the same file into lib/stmpregs.c?

Fine with me in general, except that I'd go for lib/stmp_device.c.

-- 
Pengutronix e.K.                           | Wolfram Sang                |
Industrial Linux Solutions                 | http://www.pengutronix.de/  |
-------------- next part --------------
A non-text attachment was scrubbed...
Name: signature.asc
Type: application/pgp-signature
Size: 198 bytes
Desc: Digital signature
URL: <http://lists.infradead.org/pipermail/linux-arm-kernel/attachments/20120309/f09d8161/attachment-0001.sig>

[PATCH V2 0/3] introduce stmp-style devices

[Wolfram Sang]

This series makes support for a certain type of devices mach independant. We
want that because such devices (having a special register layout) have been
found in mach-mxs and mach-mx6 meanwhile. Please refer to patch 1/3 for a more
detailed description.

Patch 1/3 adds the basic support and is of main interest to get upstream.
Patches 2/3 and 3/3 are usage examples and will be send to the relevant
subsystems once the basic support is accepted.

Main changes since the V1:

* moved stmp_device.c from drivers/base to lib/

Main changes since the RFC:

* renamed the macros to STMP_OFFSET_*
* rebased to 3.3-rc6

Tested with a TX28 board.

Thanks,

   Wolfram

Wolfram Sang (3):
  lib: add support for stmp-style devices
  i2c: mxs: use global reset function
  rtc: stmp3xxx: use global stmp_device functionality

 drivers/i2c/busses/Kconfig   |    1 +
 drivers/i2c/busses/i2c-mxs.c |    9 +----
 drivers/rtc/Kconfig          |    1 +
 drivers/rtc/rtc-stmp3xxx.c   |   29 +++++----------
 include/linux/stmp_device.h  |   20 ++++++++++
 lib/Kconfig                  |    3 ++
 lib/Makefile                 |    2 +
 lib/stmp_device.c            |   80 ++++++++++++++++++++++++++++++++++++++++++
 8 files changed, 119 insertions(+), 26 deletions(-)
 create mode 100644 include/linux/stmp_device.h
 create mode 100644 lib/stmp_device.c

-- 
1.7.2.5

[PATCH 3/3] rtc: stmp3xxx: use global stmp_device functionality

[Wolfram Sang]

The former mach specific reset_block function has been converted to a global
one. Use the new one to remove mach dependency from the driver. Also simplify
code using the new STMP_REG_* macros.

Signed-off-by: Wolfram Sang <w.sang@pengutronix.de>
---
 drivers/rtc/Kconfig        |    1 +
 drivers/rtc/rtc-stmp3xxx.c |   29 ++++++++++-------------------
 2 files changed, 11 insertions(+), 19 deletions(-)

diff --git a/drivers/rtc/Kconfig b/drivers/rtc/Kconfig
index 3a125b8..e124f93 100644
--- a/drivers/rtc/Kconfig
+++ b/drivers/rtc/Kconfig
@@ -983,6 +983,7 @@ config RTC_DRV_COH901331
 config RTC_DRV_STMP
 	tristate "Freescale STMP3xxx/i.MX23/i.MX28 RTC"
 	depends on ARCH_MXS
+	select STMP_DEVICE
 	help
 	  If you say yes here you will get support for the onboard
 	  STMP3xxx/i.MX23/i.MX28 RTC.
diff --git a/drivers/rtc/rtc-stmp3xxx.c b/drivers/rtc/rtc-stmp3xxx.c
index 1028786..e755d3e 100644
--- a/drivers/rtc/rtc-stmp3xxx.c
+++ b/drivers/rtc/rtc-stmp3xxx.c
@@ -25,11 +25,9 @@
 #include <linux/interrupt.h>
 #include <linux/rtc.h>
 #include <linux/slab.h>
-
-#include <mach/common.h>
+#include <linux/stmp_device.h>
 
 #define STMP3XXX_RTC_CTRL			0x0
-#define STMP3XXX_RTC_CTRL_SET			0x4
 #define STMP3XXX_RTC_CTRL_CLR			0x8
 #define STMP3XXX_RTC_CTRL_ALARM_IRQ_EN		0x00000001
 #define STMP3XXX_RTC_CTRL_ONEMSEC_IRQ_EN	0x00000002
@@ -44,7 +42,6 @@
 #define STMP3XXX_RTC_ALARM			0x40
 
 #define STMP3XXX_RTC_PERSISTENT0		0x60
-#define STMP3XXX_RTC_PERSISTENT0_SET		0x64
 #define STMP3XXX_RTC_PERSISTENT0_CLR		0x68
 #define STMP3XXX_RTC_PERSISTENT0_ALARM_WAKE_EN	0x00000002
 #define STMP3XXX_RTC_PERSISTENT0_ALARM_EN	0x00000004
@@ -106,20 +103,14 @@ static irqreturn_t stmp3xxx_rtc_interrupt(int irq, void *dev_id)
 static int stmp3xxx_alarm_irq_enable(struct device *dev, unsigned int enabled)
 {
 	struct stmp3xxx_rtc_data *rtc_data = dev_get_drvdata(dev);
+	u32 set_clr_offset = enabled ? STMP_OFFSET_REG_SET : STMP_OFFSET_REG_CLR;
+
+	writel(STMP3XXX_RTC_PERSISTENT0_ALARM_EN |
+		STMP3XXX_RTC_PERSISTENT0_ALARM_WAKE_EN,
+		rtc_data->io + STMP3XXX_RTC_PERSISTENT0 + set_clr_offset);
+	writel(STMP3XXX_RTC_CTRL_ALARM_IRQ_EN,
+		rtc_data->io + STMP3XXX_RTC_CTRL + set_clr_offset);
 
-	if (enabled) {
-		writel(STMP3XXX_RTC_PERSISTENT0_ALARM_EN |
-				STMP3XXX_RTC_PERSISTENT0_ALARM_WAKE_EN,
-				rtc_data->io + STMP3XXX_RTC_PERSISTENT0_SET);
-		writel(STMP3XXX_RTC_CTRL_ALARM_IRQ_EN,
-				rtc_data->io + STMP3XXX_RTC_CTRL_SET);
-	} else {
-		writel(STMP3XXX_RTC_PERSISTENT0_ALARM_EN |
-				STMP3XXX_RTC_PERSISTENT0_ALARM_WAKE_EN,
-				rtc_data->io + STMP3XXX_RTC_PERSISTENT0_CLR);
-		writel(STMP3XXX_RTC_CTRL_ALARM_IRQ_EN,
-				rtc_data->io + STMP3XXX_RTC_CTRL_CLR);
-	}
 	return 0;
 }
 
@@ -206,7 +197,7 @@ static int stmp3xxx_rtc_probe(struct platform_device *pdev)
 
 	platform_set_drvdata(pdev, rtc_data);
 
-	mxs_reset_block(rtc_data->io);
+	stmp_reset_block(rtc_data->io);
 	writel(STMP3XXX_RTC_PERSISTENT0_ALARM_EN |
 			STMP3XXX_RTC_PERSISTENT0_ALARM_WAKE_EN |
 			STMP3XXX_RTC_PERSISTENT0_ALARM_WAKE,
@@ -253,7 +244,7 @@ static int stmp3xxx_rtc_resume(struct platform_device *dev)
 {
 	struct stmp3xxx_rtc_data *rtc_data = platform_get_drvdata(dev);
 
-	mxs_reset_block(rtc_data->io);
+	stmp_reset_block(rtc_data->io);
 	writel(STMP3XXX_RTC_PERSISTENT0_ALARM_EN |
 			STMP3XXX_RTC_PERSISTENT0_ALARM_WAKE_EN |
 			STMP3XXX_RTC_PERSISTENT0_ALARM_WAKE,
-- 
1.7.2.5

[PATCH 0/3] make stmp-style devices mach-independent

[Wolfram Sang]

It seems I haven't been following the lists too closely lately, so I might have
missed similar patches. Yet, I noticed some patches dealing with drivers using
mxs-specific features, so they need to include mach-specific files which is
troublesome. I started to address the problem as well some time ago, so I push
out the patches now as RFC to enrich the discussion. The patches are rebased to
linux 3.2-rc2 and are boot tested.

The basics: mach-mxs uses ip-cores which follow a register layout I have
first seen on STMP SoCs. That means, every register has four incarnations:
 - one u32 to store a value
 - a SET register where every 1-bit sets the corresponding bit,
   others are unaffected
 - similar with a CLR register
 - and a TGL (toggle) register

Also, the 2 MSBs in register 0 are always the same and can be used to reset the
block.

All this is strictly speaking not mach-specific (but ip-core specific) and,
thus, doesn't need to be in mach-mxs/include. As I have been told, mx50 and
mx6(?) might also use IP cores following the STMP-style; so I wondered if it
can't be exported like the following patch series does:

Introduce a stmp-style device, put the code around that in a public place
(currently drivers/base/; dunno if that is the best place, though), and let
drivers for stmp-style devices select that code.

Voila, mach dependency gone, reusable code introduced. Note that I didn't
remove the duplicated code from mach-mxs yet, first all drivers have to be
converted.

Right thing to do? If so, I'll repost properly to the right lists. Fishing for
feedback right now :)

Thanks,

   Wolfram

Wolfram Sang (3):
  drivers: base: add support for stmp-style devices
  i2c: mxs: use global reset function
  rtc: stmp3xxx: use global stmp_device functionality

 drivers/base/Kconfig         |    3 ++
 drivers/base/Makefile        |    1 +
 drivers/base/stmp_device.c   |   80 ++++++++++++++++++++++++++++++++++++++++++
 drivers/i2c/busses/Kconfig   |    1 +
 drivers/i2c/busses/i2c-mxs.c |    9 +----
 drivers/rtc/Kconfig          |    1 +
 drivers/rtc/rtc-stmp3xxx.c   |   29 +++++----------
 include/linux/stmp_device.h  |   19 ++++++++++
 8 files changed, 117 insertions(+), 26 deletions(-)
 create mode 100644 drivers/base/stmp_device.c
 create mode 100644 include/linux/stmp_device.h

-- 
1.7.7.1

[PATCH 3/3] rtc: stmp3xxx: use global stmp_device functionality

[Wolfram Sang]

The former mach specific reset_block function has been converted to a global
one. Use the new one to remove mach dependency from the driver. Also simplify
code using the new STMP_REG_* macros.

Signed-off-by: Wolfram Sang <w.sang@pengutronix.de>
---
 drivers/rtc/Kconfig        |    1 +
 drivers/rtc/rtc-stmp3xxx.c |   29 ++++++++++-------------------
 2 files changed, 11 insertions(+), 19 deletions(-)

diff --git a/drivers/rtc/Kconfig b/drivers/rtc/Kconfig
index 53eb4e5..babdd5d 100644
--- a/drivers/rtc/Kconfig
+++ b/drivers/rtc/Kconfig
@@ -983,6 +983,7 @@ config RTC_DRV_COH901331
 config RTC_DRV_STMP
 	tristate "Freescale STMP3xxx/i.MX23/i.MX28 RTC"
 	depends on ARCH_MXS
+	select STMP_DEVICE
 	help
 	  If you say yes here you will get support for the onboard
 	  STMP3xxx/i.MX23/i.MX28 RTC.
diff --git a/drivers/rtc/rtc-stmp3xxx.c b/drivers/rtc/rtc-stmp3xxx.c
index 7315068..23db0ed 100644
--- a/drivers/rtc/rtc-stmp3xxx.c
+++ b/drivers/rtc/rtc-stmp3xxx.c
@@ -25,11 +25,9 @@
 #include <linux/interrupt.h>
 #include <linux/rtc.h>
 #include <linux/slab.h>
-
-#include <mach/common.h>
+#include <linux/stmp_device.h>
 
 #define STMP3XXX_RTC_CTRL			0x0
-#define STMP3XXX_RTC_CTRL_SET			0x4
 #define STMP3XXX_RTC_CTRL_CLR			0x8
 #define STMP3XXX_RTC_CTRL_ALARM_IRQ_EN		0x00000001
 #define STMP3XXX_RTC_CTRL_ONEMSEC_IRQ_EN	0x00000002
@@ -44,7 +42,6 @@
 #define STMP3XXX_RTC_ALARM			0x40
 
 #define STMP3XXX_RTC_PERSISTENT0		0x60
-#define STMP3XXX_RTC_PERSISTENT0_SET		0x64
 #define STMP3XXX_RTC_PERSISTENT0_CLR		0x68
 #define STMP3XXX_RTC_PERSISTENT0_ALARM_WAKE_EN	0x00000002
 #define STMP3XXX_RTC_PERSISTENT0_ALARM_EN	0x00000004
@@ -106,20 +103,14 @@ static irqreturn_t stmp3xxx_rtc_interrupt(int irq, void *dev_id)
 static int stmp3xxx_alarm_irq_enable(struct device *dev, unsigned int enabled)
 {
 	struct stmp3xxx_rtc_data *rtc_data = dev_get_drvdata(dev);
+	u32 set_clr_offset = enabled ? STMP_SET_ADDR : STMP_CLR_ADDR;
+
+	writel(STMP3XXX_RTC_PERSISTENT0_ALARM_EN |
+		STMP3XXX_RTC_PERSISTENT0_ALARM_WAKE_EN,
+		rtc_data->io + STMP3XXX_RTC_PERSISTENT0 + set_clr_offset);
+	writel(STMP3XXX_RTC_CTRL_ALARM_IRQ_EN,
+		rtc_data->io + STMP3XXX_RTC_CTRL + set_clr_offset);
 
-	if (enabled) {
-		writel(STMP3XXX_RTC_PERSISTENT0_ALARM_EN |
-				STMP3XXX_RTC_PERSISTENT0_ALARM_WAKE_EN,
-				rtc_data->io + STMP3XXX_RTC_PERSISTENT0_SET);
-		writel(STMP3XXX_RTC_CTRL_ALARM_IRQ_EN,
-				rtc_data->io + STMP3XXX_RTC_CTRL_SET);
-	} else {
-		writel(STMP3XXX_RTC_PERSISTENT0_ALARM_EN |
-				STMP3XXX_RTC_PERSISTENT0_ALARM_WAKE_EN,
-				rtc_data->io + STMP3XXX_RTC_PERSISTENT0_CLR);
-		writel(STMP3XXX_RTC_CTRL_ALARM_IRQ_EN,
-				rtc_data->io + STMP3XXX_RTC_CTRL_CLR);
-	}
 	return 0;
 }
 
@@ -206,7 +197,7 @@ static int stmp3xxx_rtc_probe(struct platform_device *pdev)
 
 	platform_set_drvdata(pdev, rtc_data);
 
-	mxs_reset_block(rtc_data->io);
+	stmp_reset_block(rtc_data->io);
 	writel(STMP3XXX_RTC_PERSISTENT0_ALARM_EN |
 			STMP3XXX_RTC_PERSISTENT0_ALARM_WAKE_EN |
 			STMP3XXX_RTC_PERSISTENT0_ALARM_WAKE,
@@ -253,7 +244,7 @@ static int stmp3xxx_rtc_resume(struct platform_device *dev)
 {
 	struct stmp3xxx_rtc_data *rtc_data = platform_get_drvdata(dev);
 
-	mxs_reset_block(rtc_data->io);
+	stmp_reset_block(rtc_data->io);
 	writel(STMP3XXX_RTC_PERSISTENT0_ALARM_EN |
 			STMP3XXX_RTC_PERSISTENT0_ALARM_WAKE_EN |
 			STMP3XXX_RTC_PERSISTENT0_ALARM_WAKE,
-- 
1.7.7.1