[v2,10/17] i2c: add locomo i2c driver
diff mbox

Message ID 1430178954-11138-11-git-send-email-dbaryshkov@gmail.com
State New
Headers show

Commit Message

Dmitry Eremin-Solenikov April 27, 2015, 11:55 p.m. UTC
LoCoMo chip contains a tiny i2c controller destined to control
M62332 DAC. Provide a separate I2C driver for this cell.

Signed-off-by: Dmitry Eremin-Solenikov <dbaryshkov@gmail.com>
---
 drivers/i2c/busses/Kconfig      |  12 ++++
 drivers/i2c/busses/Makefile     |   1 +
 drivers/i2c/busses/i2c-locomo.c | 136 ++++++++++++++++++++++++++++++++++++++++
 3 files changed, 149 insertions(+)
 create mode 100644 drivers/i2c/busses/i2c-locomo.c

Comments

Wolfram Sang May 12, 2015, 7:24 p.m. UTC | #1
On Tue, Apr 28, 2015 at 02:55:47AM +0300, Dmitry Eremin-Solenikov wrote:
> LoCoMo chip contains a tiny i2c controller destined to control
> M62332 DAC. Provide a separate I2C driver for this cell.
> 
> Signed-off-by: Dmitry Eremin-Solenikov <dbaryshkov@gmail.com>

Thanks for the submission!

> +#include <linux/kernel.h>
> +#include <linux/module.h>
> +#include <linux/platform_device.h>
> +#include <linux/regmap.h>
> +#include <linux/slab.h>
> +#include <linux/mfd/locomo.h>
> +
> +#include <linux/i2c.h>
> +#include <linux/i2c-algo-bit.h>

To avoid duplicates, I prefer the includes to be sorted. No need to
resend because of that, though.

Kudos for brushing up old code! Do you want the drivers go via the
subsystem trees? Or is there a dependency so it should go in via some
other tree in one go?
Dmitry Eremin-Solenikov May 12, 2015, 7:27 p.m. UTC | #2
2015-05-12 22:24 GMT+03:00 Wolfram Sang <wsa@the-dreams.de>:
> On Tue, Apr 28, 2015 at 02:55:47AM +0300, Dmitry Eremin-Solenikov wrote:
>> LoCoMo chip contains a tiny i2c controller destined to control
>> M62332 DAC. Provide a separate I2C driver for this cell.
>>
>> Signed-off-by: Dmitry Eremin-Solenikov <dbaryshkov@gmail.com>
>
> Thanks for the submission!
>
>> +#include <linux/kernel.h>
>> +#include <linux/module.h>
>> +#include <linux/platform_device.h>
>> +#include <linux/regmap.h>
>> +#include <linux/slab.h>
>> +#include <linux/mfd/locomo.h>
>> +
>> +#include <linux/i2c.h>
>> +#include <linux/i2c-algo-bit.h>
>
> To avoid duplicates, I prefer the includes to be sorted. No need to
> resend because of that, though.
>
> Kudos for brushing up old code! Do you want the drivers go via the
> subsystem trees? Or is there a dependency so it should go in via some
> other tree in one go?

There is a header dependency -- <linux/mfd/locomo.h> is a new header.
I'd prefer for these patches to go in via one of MFD, arm-soc or ARM trees
as a whole series (if that would be ok with respective maintainers).
Wolfram Sang May 12, 2015, 7:28 p.m. UTC | #3
On Tue, May 12, 2015 at 10:27:07PM +0300, Dmitry Eremin-Solenikov wrote:
> 2015-05-12 22:24 GMT+03:00 Wolfram Sang <wsa@the-dreams.de>:
> > On Tue, Apr 28, 2015 at 02:55:47AM +0300, Dmitry Eremin-Solenikov wrote:
> >> LoCoMo chip contains a tiny i2c controller destined to control
> >> M62332 DAC. Provide a separate I2C driver for this cell.
> >>
> >> Signed-off-by: Dmitry Eremin-Solenikov <dbaryshkov@gmail.com>
> >
> > Thanks for the submission!
> >
> >> +#include <linux/kernel.h>
> >> +#include <linux/module.h>
> >> +#include <linux/platform_device.h>
> >> +#include <linux/regmap.h>
> >> +#include <linux/slab.h>
> >> +#include <linux/mfd/locomo.h>
> >> +
> >> +#include <linux/i2c.h>
> >> +#include <linux/i2c-algo-bit.h>
> >
> > To avoid duplicates, I prefer the includes to be sorted. No need to
> > resend because of that, though.
> >
> > Kudos for brushing up old code! Do you want the drivers go via the
> > subsystem trees? Or is there a dependency so it should go in via some
> > other tree in one go?
> 
> There is a header dependency -- <linux/mfd/locomo.h> is a new header.
> I'd prefer for these patches to go in via one of MFD, arm-soc or ARM trees
> as a whole series (if that would be ok with respective maintainers).

Fine with me.

Reviewed-by: Wolfram Sang <wsa@the-dreams.de>

Patch
diff mbox

diff --git a/drivers/i2c/busses/Kconfig b/drivers/i2c/busses/Kconfig
index 2255af2..114d9da 100644
--- a/drivers/i2c/busses/Kconfig
+++ b/drivers/i2c/busses/Kconfig
@@ -602,6 +602,18 @@  config I2C_KEMPLD
 	  This driver can also be built as a module. If so, the module
 	  will be called i2c-kempld.
 
+config I2C_LOCOMO
+	tristate "I2C bus support for LoCoMo chips"
+	depends on MFD_LOCOMO
+	select I2C_ALGOBIT
+	help
+	  Say yes if you will run the kernel on Sharp SL-5x00 family of devices.
+
+	  If you don't know what to do here, say N.
+
+	  This driver can also be built as a module.  If so, the module
+	  will be called i2c-locomo.
+
 config I2C_MESON
 	tristate "Amlogic Meson I2C controller"
 	depends on ARCH_MESON
diff --git a/drivers/i2c/busses/Makefile b/drivers/i2c/busses/Makefile
index cdf941d..e09dcf6 100644
--- a/drivers/i2c/busses/Makefile
+++ b/drivers/i2c/busses/Makefile
@@ -58,6 +58,7 @@  obj-$(CONFIG_I2C_IMX)		+= i2c-imx.o
 obj-$(CONFIG_I2C_IOP3XX)	+= i2c-iop3xx.o
 obj-$(CONFIG_I2C_JZ4780)	+= i2c-jz4780.o
 obj-$(CONFIG_I2C_KEMPLD)	+= i2c-kempld.o
+obj-$(CONFIG_I2C_LOCOMO)	+= i2c-locomo.o
 obj-$(CONFIG_I2C_MESON)		+= i2c-meson.o
 obj-$(CONFIG_I2C_MPC)		+= i2c-mpc.o
 obj-$(CONFIG_I2C_MV64XXX)	+= i2c-mv64xxx.o
diff --git a/drivers/i2c/busses/i2c-locomo.c b/drivers/i2c/busses/i2c-locomo.c
new file mode 100644
index 0000000..640b46cd
--- /dev/null
+++ b/drivers/i2c/busses/i2c-locomo.c
@@ -0,0 +1,136 @@ 
+/*
+ * This program is free software; you can redistribute it and/or modify
+ * it under the terms of the GNU General Public License version 2 as
+ * published by the Free Software Foundation.
+ */
+#include <linux/kernel.h>
+#include <linux/module.h>
+#include <linux/platform_device.h>
+#include <linux/regmap.h>
+#include <linux/slab.h>
+#include <linux/mfd/locomo.h>
+
+#include <linux/i2c.h>
+#include <linux/i2c-algo-bit.h>
+
+struct locomo_i2c {
+	struct regmap		*regmap;
+	struct i2c_adapter	 adap;
+	struct i2c_algo_bit_data bit;
+};
+
+static void locomo_i2c_setsda(void *data, int state)
+{
+	struct locomo_i2c *li2c = data;
+
+	regmap_update_bits(li2c->regmap, LOCOMO_DAC,
+			LOCOMO_DAC_SDAOEB,
+			state ? LOCOMO_DAC_SDAOEB : 0);
+}
+
+static void locomo_i2c_setscl(void *data, int state)
+{
+	struct locomo_i2c *li2c = data;
+
+	regmap_update_bits(li2c->regmap, LOCOMO_DAC,
+			LOCOMO_DAC_SCLOEB,
+			state ? LOCOMO_DAC_SCLOEB : 0);
+}
+
+static int locomo_i2c_getsda(void *data)
+{
+	struct locomo_i2c *li2c = data;
+	unsigned int r;
+
+	regmap_read(li2c->regmap, LOCOMO_DAC, &r);
+
+	return !!(r & LOCOMO_DAC_SDA);
+}
+
+static int locomo_i2c_probe(struct platform_device *dev)
+{
+	struct locomo_i2c *li2c;
+	int ret;
+
+	li2c = devm_kzalloc(&dev->dev, sizeof(struct locomo_i2c), GFP_KERNEL);
+	if (li2c == NULL)
+		return -ENOMEM;
+
+	li2c->regmap = dev_get_regmap(dev->dev.parent, NULL);
+	if (!li2c->regmap)
+		return -ENODEV;
+
+	li2c->adap.owner = THIS_MODULE;
+	li2c->adap.dev.parent = &dev->dev;
+	li2c->adap.dev.of_node = dev->dev.of_node;
+	li2c->adap.algo_data = &li2c->bit;
+	li2c->adap.nr = 1; /* On poodle, 0 is pxa internal bus */
+
+	strlcpy(li2c->adap.name, "LoCoMo I2C", sizeof(li2c->adap.name));
+
+	li2c->bit.data = li2c;
+	li2c->bit.setsda = locomo_i2c_setsda;
+	li2c->bit.setscl = locomo_i2c_setscl;
+	li2c->bit.getsda = locomo_i2c_getsda;
+	li2c->bit.udelay = 6;
+	li2c->bit.timeout = HZ;
+
+	ret = i2c_bit_add_numbered_bus(&li2c->adap);
+	if (ret)
+		return ret;
+
+	platform_set_drvdata(dev, li2c);
+
+	return 0;
+}
+
+static int locomo_i2c_remove(struct platform_device *dev)
+{
+	struct locomo_i2c *li2c = platform_get_drvdata(dev);
+
+	i2c_del_adapter(&li2c->adap);
+
+	return 0;
+}
+
+#ifdef CONFIG_PM_SLEEP
+static int locomo_i2c_suspend(struct device *dev)
+{
+	struct locomo_i2c *li2c = dev_get_drvdata(dev);
+
+	regmap_write(li2c->regmap, LOCOMO_DAC, 0x00);
+
+	return 0;
+}
+
+static int locomo_i2c_resume(struct device *dev)
+{
+	struct locomo_i2c *li2c = dev_get_drvdata(dev);
+
+	regmap_write(li2c->regmap, LOCOMO_DAC,
+			LOCOMO_DAC_SDAOEB | LOCOMO_DAC_SCLOEB);
+
+	return 0;
+}
+static SIMPLE_DEV_PM_OPS(locomo_i2c_pm, locomo_i2c_suspend, locomo_i2c_resume);
+#define LOCOMO_I2C_PM	(&locomo_i2c_pm)
+#else
+#define LOCOMO_I2C_PM	NULL
+#endif
+
+
+static struct platform_driver locomo_i2c_driver = {
+	.driver		= {
+		.name	= "locomo-i2c",
+		.pm	= LOCOMO_I2C_PM,
+	},
+	.probe		= locomo_i2c_probe,
+	.remove		= locomo_i2c_remove,
+};
+
+module_platform_driver(locomo_i2c_driver);
+
+MODULE_DESCRIPTION("LoCoMo i2c bus driver");
+MODULE_AUTHOR("Dmitry Eremin-Solenikov <dbaryshkov@gmail.com>");
+MODULE_LICENSE("GPL v2");
+MODULE_ALIAS("platform:locomo-i2c");