diff mbox

[PATCHv2,2/3] sunxi:drivers:input:ps2 Added sunxi A10/A20 ps2 driver

Message ID 1417907719-26775-3-git-send-email-VishnuPatekar0510@gmail.com (mailing list archive)
State New, archived
Headers show

Commit Message

vishnupatekar Dec. 6, 2014, 11:15 p.m. UTC
-added compatible as allwinner,sun4i-a10-ps2 and allwinner,sun7i-a20-ps2.
 - added default n depends on ARCH_SUNXI || COMPILE_TEST
 in Kconfig.
 -handled errors and free resources on errors.
 -used BIT(x), DIV_ROUND_UP macros.
 -corrected style errors.

Signed-off-by: vishnupatekar <VishnuPatekar0510@gmail.com>
---
 drivers/input/serio/Kconfig     |   10 ++
 drivers/input/serio/Makefile    |    1 +
 drivers/input/serio/sunxi-ps2.c |  364 +++++++++++++++++++++++++++++++++++++++
 3 files changed, 375 insertions(+)
 create mode 100644 drivers/input/serio/sunxi-ps2.c

Comments

Maxime Ripard Dec. 8, 2014, 10:41 p.m. UTC | #1
Hi,

On Sun, Dec 07, 2014 at 04:45:18AM +0530, vishnupatekar wrote:
>  -added compatible as allwinner,sun4i-a10-ps2 and allwinner,sun7i-a20-ps2.
>  - added default n depends on ARCH_SUNXI || COMPILE_TEST
>  in Kconfig.
>  -handled errors and free resources on errors.
>  -used BIT(x), DIV_ROUND_UP macros.
>  -corrected style errors.

The changelog should be either in your cover letter or just above the
diffstat, but not in your commitlog.

This should have a real commit log, telling what you're doing, why,
and how.

> Signed-off-by: vishnupatekar <VishnuPatekar0510@gmail.com>
> ---
>  drivers/input/serio/Kconfig     |   10 ++
>  drivers/input/serio/Makefile    |    1 +
>  drivers/input/serio/sunxi-ps2.c |  364 +++++++++++++++++++++++++++++++++++++++
>  3 files changed, 375 insertions(+)
>  create mode 100644 drivers/input/serio/sunxi-ps2.c
> 
> diff --git a/drivers/input/serio/Kconfig b/drivers/input/serio/Kconfig
> index bc2d474..3a7599c 100644
> --- a/drivers/input/serio/Kconfig
> +++ b/drivers/input/serio/Kconfig
> @@ -281,4 +281,14 @@ config HYPERV_KEYBOARD
>  	  To compile this driver as a module, choose M here: the module will
>  	  be called hyperv_keyboard.
>  
> +config SERIO_SUNXI_PS2
> +	tristate "Allwinner Sun4i-A10/Sun7i-A20 PS/2 controller"

Allwinner A10 is enough

> +	default n

This is the default.

> +	depends on ARCH_SUNXI || COMPILE_TEST
> +	help
> +	  Say Y here if you have Sun4i-A10/Sun7i-A20 Allwinner PS/2 ports.

You can just mention Allwinne A10 here, on sun4i, at your convenience.

> +
> +	  To compile this driver as a module, choose M here: the
> +	  module will be called sunxi-ps2.
> +
>  endif
> diff --git a/drivers/input/serio/Makefile b/drivers/input/serio/Makefile
> index 815d874..0fa0f78 100644
> --- a/drivers/input/serio/Makefile
> +++ b/drivers/input/serio/Makefile
> @@ -29,3 +29,4 @@ obj-$(CONFIG_SERIO_ARC_PS2)	+= arc_ps2.o
>  obj-$(CONFIG_SERIO_APBPS2)	+= apbps2.o
>  obj-$(CONFIG_SERIO_OLPC_APSP)	+= olpc_apsp.o
>  obj-$(CONFIG_HYPERV_KEYBOARD)	+= hyperv-keyboard.o
> +obj-$(CONFIG_SERIO_SUNXI_PS2)	+= sunxi-ps2.o
> diff --git a/drivers/input/serio/sunxi-ps2.c b/drivers/input/serio/sunxi-ps2.c
> new file mode 100644
> index 0000000..4cd89ae
> --- /dev/null
> +++ b/drivers/input/serio/sunxi-ps2.c

Please call it sun4i-ps2, just in case we have another one coming at
some point.

> @@ -0,0 +1,364 @@
> +/*
> + *	Driver for Allwinner A20 PS2 host controller

s/A20/A10/ ?

> + *	Author: Vishnu Patekar <vishnupatekar0510@gmail.com>
> + *		Aaron.maoye <leafy.myeh@newbietech.com>
> + *
> + *		Based on 3.0 kernel

Please mention that it is Allwinner's kernel driver you're talking
about.

> + *
> + */
> +
> +#include <linux/module.h>
> +#include <linux/serio.h>
> +#include <linux/interrupt.h>
> +#include <linux/errno.h>
> +#include <linux/slab.h>
> +#include <linux/list.h>
> +#include <linux/io.h>
> +#include <linux/of_address.h>
> +#include <linux/of_device.h>
> +#include <linux/of_irq.h>
> +#include <linux/of_platform.h>
> +#include <linux/clk.h>
> +#include <linux/delay.h>
> +
> +#define DRIVER_NAME		"sunxi-ps2"
> +
> +/* register offset definitions */
> +#define PS2_REG_GCTL		(0x00)	/*  PS2 Module Global Control Reg */
> +#define PS2_REG_DATA		(0x04)  /*  PS2 Module Data Reg		*/
> +#define PS2_REG_LCTL		(0x08)	/*  PS2 Module Line Control Reg */
> +#define PS2_REG_LSTS		(0x0C)  /*  PS2 Module Line Status Reg	*/
> +#define PS2_REG_FCTL		(0x10)	/*  PS2 Module FIFO Control Reg */
> +#define PS2_REG_FSTS		(0x14)	/*  PS2 Module FIFO Status Reg	*/
> +#define PS2_REG_CLKDR		(0x18)	/*  PS2 Module Clock Divider Reg*/
> +
> +/*  PS2 GLOBAL CONTROL REGISTER PS2_GCTL */
> +#define PS2_GCTL_INTFLAG	BIT(4)
> +#define PS2_GCTL_INTEN		BIT(3)
> +#define PS2_GCTL_RESET		BIT(2)
> +#define PS2_GCTL_MASTER		BIT(1)
> +#define PS2_GCTL_BUSEN		BIT(0)
> +
> +/* PS2 LINE CONTROL REGISTER */
> +#define PS2_LCTL_NOACK		BIT(18)
> +#define PS2_LCTL_TXDTOEN	BIT(8)
> +#define PS2_LCTL_STOPERREN	BIT(3)
> +#define PS2_LCTL_ACKERREN	BIT(2)
> +#define PS2_LCTL_PARERREN	BIT(1)
> +#define PS2_LCTL_RXDTOEN	BIT(0)
> +
> +/* PS2 LINE STATUS REGISTER */
> +#define PS2_LSTS_TXTDO		BIT(8)
> +#define PS2_LSTS_STOPERR	BIT(3)
> +#define PS2_LSTS_ACKERR		BIT(2)
> +#define PS2_LSTS_PARERR		BIT(1)
> +#define PS2_LSTS_RXTDO		BIT(0)
> +
> +/* PS2 FIFO CONTROL REGISTER */
> +#define PS2_FCTL_TXRST		BIT(17)
> +#define PS2_FCTL_RXRST		BIT(16)
> +#define PS2_FCTL_TXUFIEN	BIT(10)
> +#define PS2_FCTL_TXOFIEN	BIT(9)
> +#define PS2_FCTL_TXRDYIEN	BIT(8)
> +#define PS2_FCTL_RXUFIEN	BIT(2)
> +#define PS2_FCTL_RXOFIEN	BIT(1)
> +#define PS2_FCTL_RXRDYIEN	BIT(0)
> +
> +/* PS2 FIFO STATUS REGISTER */
> +#define PS2_FSTS_TXUF		BIT(10)
> +#define PS2_FSTS_TXOF		BIT(9)
> +#define PS2_FSTS_TXRDY		BIT(8)
> +#define PS2_FSTS_RXUF		BIT(2)
> +#define PS2_FSTS_RXOF		BIT(1)
> +#define PS2_FSTS_RXRDY		BIT(0)

Please define the bits right below the register they belong too, not
separated.

> +#define PS2_LINE_ERROR_BIT \
> +	(PS2_LSTS_TXTDO|PS2_LSTS_STOPERR|PS2_LSTS_ACKERR| \
> +	PS2_LSTS_PARERR|PS2_LSTS_RXTDO)
> +
> +#define PS2_FIFO_ERROR_BIT \
> +	(PS2_FSTS_TXUF|PS2_FSTS_TXOF|PS2_FSTS_TXRDY|PS2_FSTS_RXUF| \
> +	PS2_FSTS_RXOF|PS2_FSTS_RXRDY)

Spaces around the operators.

> +
> +#define PS2_SAMPLE_CLK		(1000000)
> +#define PS2_SCLK		(125000)
> +
> +struct sunxips2data {
> +	struct serio *serio;
> +	struct device *dev;
> +
> +	/* IO mapping base */
> +	void __iomem	*reg_base;
> +
> +	/* clock management */
> +	struct clk	*clk;
> +
> +	/* irq */
> +	spinlock_t	lock;
> +	int		irq;
> +};
> +
> +/*********************/
> +/* Interrupt handler */
> +/*********************/
> +static irqreturn_t sunxips2_interrupt(int irq, void *dev_id)

s/sunxips2/sun4i_ps2/ please.

> +{
> +	struct sunxips2data *drvdata = dev_id;
> +	u32 intr_status;
> +	u32 fifo_status;
> +	unsigned char byte;
> +	u32 rval;
> +	u32 error = 0;
> +
> +	spin_lock(&drvdata->lock);
> +
> +	/* Get the PS/2 interrupts and clear them */
> +	intr_status  = readl(drvdata->reg_base + PS2_REG_LSTS);
> +	fifo_status  = readl(drvdata->reg_base + PS2_REG_FSTS);
> +
> +	/*Check Line Status Register*/
> +	if (intr_status & 0x10f) {
> +		if (intr_status & PS2_LSTS_STOPERR)
> +			dev_info(drvdata->dev, "PS/2 Stop Bit Error!");
> +		if (intr_status & PS2_LSTS_ACKERR)
> +			dev_info(drvdata->dev, "PS/2 Acknowledge Error!\n");
> +		if (intr_status & PS2_LSTS_PARERR)
> +			dev_info(drvdata->dev, "PS/2 Parity Error!\n");
> +		if (intr_status & PS2_LSTS_TXTDO)
> +			dev_info(drvdata->dev, "PS/2 Transmit Data Timeout!\n");
> +		if (intr_status & PS2_LSTS_RXTDO)
> +			dev_info(drvdata->dev, "PS/2 Receive Data Timeout!\n");
> +
> +		/*reset PS/2 controller*/
> +		writel(readl(drvdata->reg_base + PS2_REG_GCTL) | PS2_GCTL_RESET,
> +			drvdata->reg_base + PS2_REG_GCTL);

It's usually better to have it as two lines: one for the read, one for
the write.

> +
> +		rval = PS2_LSTS_TXTDO | PS2_LSTS_STOPERR | PS2_LSTS_ACKERR |
> +			PS2_LSTS_PARERR | PS2_LSTS_RXTDO;
> +		writel(rval, drvdata->reg_base + PS2_REG_LSTS);
> +		error = 1;
> +	}
> +
> +	/*Check FIFO Status Register*/
> +	if (fifo_status & 0x0606) {
> +		if (fifo_status & PS2_FSTS_TXUF)
> +			dev_info(drvdata->dev, "PS/2 Tx FIFO Underflow!\n");
> +		if (fifo_status & PS2_FSTS_TXOF)
> +			dev_info(drvdata->dev, "PS/2 Tx FIFO Overflow!\n");
> +		if (fifo_status & PS2_FSTS_RXUF)
> +			dev_info(drvdata->dev, "PS/2 Rx FIFO Underflow!\n");
> +		if (fifo_status & PS2_FSTS_RXOF)
> +			dev_info(drvdata->dev, "PS/2 Rx FIFO Overflow!\n");
> +		/*reset PS/2 controller*/
> +		writel(readl(drvdata->reg_base + PS2_REG_GCTL) | PS2_GCTL_RESET,
> +			drvdata->reg_base + PS2_REG_GCTL);

Ditto.

> +		rval = PS2_FSTS_TXUF | PS2_FSTS_TXOF | PS2_FSTS_TXRDY |
> +			PS2_FSTS_RXUF | PS2_FSTS_RXOF | PS2_FSTS_RXRDY;
> +		writel(rval, drvdata->reg_base + PS2_REG_FSTS);
> +		error = 1;
> +	}
> +
> +	rval = (fifo_status >> 16) & 0x3;
> +	while (!error && rval--) {
> +		byte = readl(drvdata->reg_base + PS2_REG_DATA) & 0xff;
> +		/* dev_info(drvdata->dev, "PS/2 Receive %02x\n", byte); */

Remove that line.

> +		serio_interrupt(drvdata->serio, byte, 0);
> +	}
> +
> +	writel(intr_status, drvdata->reg_base + PS2_REG_LSTS);
> +	writel(fifo_status, drvdata->reg_base + PS2_REG_FSTS);
> +
> +	spin_unlock(&drvdata->lock);
> +
> +	return IRQ_HANDLED;
> +}
> +
> +
> +static int sunxips2_open(struct serio *pserio)
> +{
> +	struct sunxips2data *drvdata = pserio->port_data;
> +	u32 src_clk = 0;
> +	u32 clk_scdf;
> +	u32 clk_pcdf;
> +	u32 rval;
> +
> +	/*Set Line Control And Enable Interrupt*/
> +	rval = PS2_LCTL_TXDTOEN | PS2_LCTL_STOPERREN | PS2_LCTL_ACKERREN
> +		| PS2_LCTL_PARERREN | PS2_LCTL_RXDTOEN;
> +	writel(rval, drvdata->reg_base + PS2_REG_LCTL);
> +
> +	/*Reset FIFO*/
> +	rval = PS2_FCTL_TXRST|PS2_FCTL_RXRST|PS2_FCTL_TXUFIEN|PS2_FCTL_TXOFIEN
> +		|PS2_FCTL_RXUFIEN|PS2_FCTL_RXOFIEN|PS2_FCTL_RXRDYIEN;
> +	writel(rval, drvdata->reg_base + PS2_REG_FCTL);
> +
> +	src_clk = clk_get_rate(drvdata->clk);
> +
> +	if (!src_clk) {
> +		dev_info(drvdata->dev, "w_ps2c_set_sclk error, source clock is 0.");
> +		return -1;
> +	}
> +
> +	/*Set Clock Divider Register*/
> +	clk_scdf = DIV_ROUND_UP(src_clk, PS2_SAMPLE_CLK) - 1;
> +	clk_pcdf = DIV_ROUND_UP(PS2_SAMPLE_CLK, PS2_SCLK) - 1;

So this is actually a rounding down?

Why not just using src_clk / PS2_SAMPLE_CLK directly?

> +	rval = (clk_scdf<<8) | clk_pcdf;

Spaces between the operators. Remember, run checkpatch.

> +	writel(rval, drvdata->reg_base + PS2_REG_CLKDR);
> +
> +	/*Set Global Control Register*/
> +	rval = PS2_GCTL_RESET | PS2_GCTL_INTEN | PS2_GCTL_MASTER
> +		| PS2_GCTL_BUSEN;
> +	writel(rval, drvdata->reg_base + PS2_REG_GCTL);

You seem to be reading/writing from the same registers than in your
interrupt handler, don't you need some locking in here?

> +
> +	return 0;
> +}
> +
> +static void sunxips2_close(struct serio *pserio)
> +{
> +	struct sunxips2data *drvdata = pserio->port_data;
> +	unsigned long flags;
> +
> +	spin_lock_irqsave(&drvdata->lock, flags);
> +	/* Disable the PS2 interrupts */
> +	writel(0, drvdata->reg_base + PS2_REG_GCTL);
> +	spin_unlock_irqrestore(&drvdata->lock, flags);
> +}
> +
> +static int sunxips2_write(struct serio *pserio, unsigned char val)
> +{
> +	unsigned long expire = jiffies + msecs_to_jiffies(10000);
> +	struct sunxips2data *drvdata = (struct sunxips2data *)pserio->port_data;
> +
> +	do {
> +		if (readl(drvdata->reg_base + PS2_REG_FSTS) & PS2_FSTS_TXRDY) {
> +			writel(val, drvdata->reg_base + PS2_REG_DATA);
> +			return 0;
> +		}
> +	} while (time_before(jiffies, expire));
> +
> +	return 0;
> +}
> +
> +static int sunxips2_probe(struct platform_device *pdev)
> +{
> +	struct resource *res; /* IO mem resources */
> +	struct sunxips2data *drvdata;
> +	struct serio *serio;
> +	struct device *dev = &pdev->dev;
> +	unsigned int irq;
> +	int error;
> +
> +	drvdata = devm_kzalloc(dev, sizeof(struct sunxips2data), GFP_KERNEL);
> +	serio = kzalloc(sizeof(struct serio), GFP_KERNEL);
> +	if (!drvdata || !serio) {
> +		error = -ENOMEM;
> +		goto err_free_mem;
> +	}
> +
> +	spin_lock_init(&drvdata->lock);
> +
> +	/* IO */
> +	res = platform_get_resource(pdev, IORESOURCE_MEM, 0);
> +	drvdata->reg_base = devm_ioremap_resource(dev, res);
> +	if (IS_ERR(drvdata->reg_base)) {
> +		dev_err(dev, "failed to map registers\n");
> +		error = PTR_ERR(drvdata->reg_base);
> +		goto err_free_mem;
> +	}
> +
> +	drvdata->clk = devm_clk_get(dev, NULL);
> +	if (!IS_ERR(drvdata->clk)) {
> +		error = clk_prepare_enable(drvdata->clk);
> +		if (error < 0) {
> +			dev_err(dev, "failed to enable clock %d\n", error);
> +			goto err_free_mem;
> +		}
> +	} else {
> +		error = PTR_ERR(drvdata->clk);
> +		dev_err(dev, "couldn't get clock %d\n", error);
> +		goto err_free_mem;
> +	}

That would be better if you had something like

clk_get()
if (IS_ERR())
  goto

clk_prepare_enable()
if (IS_ERR())

Especially since you're using that kind of construct in the rest of
your function.

> +	serio->id.type = SERIO_8042;
> +	serio->write = sunxips2_write;
> +	serio->open = sunxips2_open;
> +	serio->close = sunxips2_close;
> +	serio->port_data = drvdata;
> +	serio->dev.parent = dev;
> +	strlcpy(serio->name, dev_name(dev), sizeof(serio->name));
> +	strlcpy(serio->phys, dev_name(dev), sizeof(serio->phys));
> +
> +	/* Get IRQ for the device */
> +	irq = platform_get_irq(pdev, 0);
> +	if (!irq) {
> +		dev_err(dev, "no IRQ found\n");
> +		error = -ENXIO;
> +		goto error_disable_clk;
> +	}
> +
> +	drvdata->irq = irq;
> +	drvdata->serio = serio;
> +	drvdata->dev = dev;
> +	error = devm_request_threaded_irq(dev, drvdata->irq,
> +		sunxips2_interrupt, NULL, 0, DRIVER_NAME, drvdata);

This really looks like a case for a regular request_irq.

> +	if (error) {
> +		dev_err(drvdata->dev, "Interrupt alloc failed %d:error:%d\n",
> +			drvdata->irq, error);
> +		goto error_disable_clk;
> +	}
> +
> +	serio_register_port(serio);
> +	platform_set_drvdata(pdev, drvdata);
> +
> +	return 0;	/* success */
> +
> +error_disable_clk:
> +	clk_disable_unprepare(drvdata->clk);
> +
> +err_free_mem:
> +	kfree(serio);
> +	return error;
> +}
> +
> +static int sunxips2_remove(struct platform_device *pdev)
> +{
> +	struct sunxips2data *drvdata = platform_get_drvdata(pdev);
> +
> +	serio_unregister_port(drvdata->serio);
> +	disable_irq(drvdata->irq);
> +
> +	if (!IS_ERR(drvdata->clk))
> +		clk_disable_unprepare(drvdata->clk);

And you can drop that if.

> +	kfree(drvdata->serio);
> +
> +	return 0;
> +}
> +
> +/* Match table for of_platform binding */
> +static const struct of_device_id sunxips2_of_match[] = {
> +	{ .compatible = "allwinner,sun7i-a20-ps2", },
> +	{ .compatible = "allwinner,sun4i-a10-ps2", },

If the two really are compatible, you just need one of them, the A10
one in that case, since that's the earlier SoCs.

> +	{ },
> +};
> +
> +MODULE_DEVICE_TABLE(of, sunxips2_of_match);
> +
> +/*platform driver structure*/
> +static struct platform_driver sunxips2_of_driver = {
> +	.probe		= sunxips2_probe,
> +	.remove		= sunxips2_remove,
> +	.driver = {
> +		.name = DRIVER_NAME,
> +		.of_match_table = sunxips2_of_match,
> +	},
> +};
> +module_platform_driver(sunxips2_of_driver);
> +
> +MODULE_AUTHOR("Vishnu Patekar <vishnupatekar0510@gmail.com>");
> +MODULE_AUTHOR("Aaron.maoye <leafy.myeh@newbietech.com>");
> +MODULE_DESCRIPTION("Sunxi PS/2 driver");
> +MODULE_LICENSE("GPL");
> -- 
> 1.7.9.5
> 

It's looking great otherwise.

Thanks!
Maxime
Maxime Ripard Dec. 11, 2014, 9:09 p.m. UTC | #2
Hi,

Remember to reply to all the recipients.

On Tue, Dec 09, 2014 at 04:40:36PM +0530, Vishnu Patekar wrote:
> > > Signed-off-by: vishnupatekar <VishnuPatekar0510@gmail.com>
> > > ---
> > >  drivers/input/serio/Kconfig     |   10 ++
> > >  drivers/input/serio/Makefile    |    1 +
> > >  drivers/input/serio/sunxi-ps2.c |  364
> > +++++++++++++++++++++++++++++++++++++++
> > >  3 files changed, 375 insertions(+)
> > >  create mode 100644 drivers/input/serio/sunxi-ps2.c
> > >
> > > diff --git a/drivers/input/serio/Kconfig b/drivers/input/serio/Kconfig
> > > index bc2d474..3a7599c 100644
> > > --- a/drivers/input/serio/Kconfig
> > > +++ b/drivers/input/serio/Kconfig
> > > @@ -281,4 +281,14 @@ config HYPERV_KEYBOARD
> > >         To compile this driver as a module, choose M here: the module
> > will
> > >         be called hyperv_keyboard.
> > >
> > > +config SERIO_SUNXI_PS2
> > > +     tristate "Allwinner Sun4i-A10/Sun7i-A20 PS/2 controller"
> >
> > Allwinner A10 is enough
> >
> Okie, Should I change the config option as well, like SERIO_SUN4I_PS2 ?

Yep.

> > > +     /*Set Clock Divider Register*/
> > > +     clk_scdf = DIV_ROUND_UP(src_clk, PS2_SAMPLE_CLK) - 1;
> > > +     clk_pcdf = DIV_ROUND_UP(PS2_SAMPLE_CLK, PS2_SCLK) - 1;
> >
> > So this is actually a rounding down?
> >
> > Why not just using src_clk / PS2_SAMPLE_CLK directly?
> >
> > > +     rval = (clk_scdf<<8) | clk_pcdf;
> >
> > Spaces between the operators. Remember, run checkpatch.
> >
> Okie.
> 
> checkpatch could  not catch this!!

Well, then it should have :)

> > > +     writel(rval, drvdata->reg_base + PS2_REG_CLKDR);
> > > +
> > > +     /*Set Global Control Register*/
> > > +     rval = PS2_GCTL_RESET | PS2_GCTL_INTEN | PS2_GCTL_MASTER
> > > +             | PS2_GCTL_BUSEN;
> > > +     writel(rval, drvdata->reg_base + PS2_REG_GCTL);
> >
> > You seem to be reading/writing from the same registers than in your
> > interrupt handler, don't you need some locking in here?
> >
>
> Interrupt is getting enabled only after writing to GCTL register.
>
> do you think still we need to locking mechanism here?

Not really, you don't know the state of the device before your driver
is probed, and the interrupts are enabled as soon as request_irq. So
you can very well have the device running with the interrupts running
before this function is called.

Plus you might get spurious interrupts.

Maxime
diff mbox

Patch

diff --git a/drivers/input/serio/Kconfig b/drivers/input/serio/Kconfig
index bc2d474..3a7599c 100644
--- a/drivers/input/serio/Kconfig
+++ b/drivers/input/serio/Kconfig
@@ -281,4 +281,14 @@  config HYPERV_KEYBOARD
 	  To compile this driver as a module, choose M here: the module will
 	  be called hyperv_keyboard.
 
+config SERIO_SUNXI_PS2
+	tristate "Allwinner Sun4i-A10/Sun7i-A20 PS/2 controller"
+	default n
+	depends on ARCH_SUNXI || COMPILE_TEST
+	help
+	  Say Y here if you have Sun4i-A10/Sun7i-A20 Allwinner PS/2 ports.
+
+	  To compile this driver as a module, choose M here: the
+	  module will be called sunxi-ps2.
+
 endif
diff --git a/drivers/input/serio/Makefile b/drivers/input/serio/Makefile
index 815d874..0fa0f78 100644
--- a/drivers/input/serio/Makefile
+++ b/drivers/input/serio/Makefile
@@ -29,3 +29,4 @@  obj-$(CONFIG_SERIO_ARC_PS2)	+= arc_ps2.o
 obj-$(CONFIG_SERIO_APBPS2)	+= apbps2.o
 obj-$(CONFIG_SERIO_OLPC_APSP)	+= olpc_apsp.o
 obj-$(CONFIG_HYPERV_KEYBOARD)	+= hyperv-keyboard.o
+obj-$(CONFIG_SERIO_SUNXI_PS2)	+= sunxi-ps2.o
diff --git a/drivers/input/serio/sunxi-ps2.c b/drivers/input/serio/sunxi-ps2.c
new file mode 100644
index 0000000..4cd89ae
--- /dev/null
+++ b/drivers/input/serio/sunxi-ps2.c
@@ -0,0 +1,364 @@ 
+/*
+ *	Driver for Allwinner A20 PS2 host controller
+ *
+ *	Author: Vishnu Patekar <vishnupatekar0510@gmail.com>
+ *		Aaron.maoye <leafy.myeh@newbietech.com>
+ *
+ *		Based on 3.0 kernel
+ *
+ */
+
+#include <linux/module.h>
+#include <linux/serio.h>
+#include <linux/interrupt.h>
+#include <linux/errno.h>
+#include <linux/slab.h>
+#include <linux/list.h>
+#include <linux/io.h>
+#include <linux/of_address.h>
+#include <linux/of_device.h>
+#include <linux/of_irq.h>
+#include <linux/of_platform.h>
+#include <linux/clk.h>
+#include <linux/delay.h>
+
+#define DRIVER_NAME		"sunxi-ps2"
+
+/* register offset definitions */
+#define PS2_REG_GCTL		(0x00)	/*  PS2 Module Global Control Reg */
+#define PS2_REG_DATA		(0x04)  /*  PS2 Module Data Reg		*/
+#define PS2_REG_LCTL		(0x08)	/*  PS2 Module Line Control Reg */
+#define PS2_REG_LSTS		(0x0C)  /*  PS2 Module Line Status Reg	*/
+#define PS2_REG_FCTL		(0x10)	/*  PS2 Module FIFO Control Reg */
+#define PS2_REG_FSTS		(0x14)	/*  PS2 Module FIFO Status Reg	*/
+#define PS2_REG_CLKDR		(0x18)	/*  PS2 Module Clock Divider Reg*/
+
+/*  PS2 GLOBAL CONTROL REGISTER PS2_GCTL */
+#define PS2_GCTL_INTFLAG	BIT(4)
+#define PS2_GCTL_INTEN		BIT(3)
+#define PS2_GCTL_RESET		BIT(2)
+#define PS2_GCTL_MASTER		BIT(1)
+#define PS2_GCTL_BUSEN		BIT(0)
+
+/* PS2 LINE CONTROL REGISTER */
+#define PS2_LCTL_NOACK		BIT(18)
+#define PS2_LCTL_TXDTOEN	BIT(8)
+#define PS2_LCTL_STOPERREN	BIT(3)
+#define PS2_LCTL_ACKERREN	BIT(2)
+#define PS2_LCTL_PARERREN	BIT(1)
+#define PS2_LCTL_RXDTOEN	BIT(0)
+
+/* PS2 LINE STATUS REGISTER */
+#define PS2_LSTS_TXTDO		BIT(8)
+#define PS2_LSTS_STOPERR	BIT(3)
+#define PS2_LSTS_ACKERR		BIT(2)
+#define PS2_LSTS_PARERR		BIT(1)
+#define PS2_LSTS_RXTDO		BIT(0)
+
+/* PS2 FIFO CONTROL REGISTER */
+#define PS2_FCTL_TXRST		BIT(17)
+#define PS2_FCTL_RXRST		BIT(16)
+#define PS2_FCTL_TXUFIEN	BIT(10)
+#define PS2_FCTL_TXOFIEN	BIT(9)
+#define PS2_FCTL_TXRDYIEN	BIT(8)
+#define PS2_FCTL_RXUFIEN	BIT(2)
+#define PS2_FCTL_RXOFIEN	BIT(1)
+#define PS2_FCTL_RXRDYIEN	BIT(0)
+
+/* PS2 FIFO STATUS REGISTER */
+#define PS2_FSTS_TXUF		BIT(10)
+#define PS2_FSTS_TXOF		BIT(9)
+#define PS2_FSTS_TXRDY		BIT(8)
+#define PS2_FSTS_RXUF		BIT(2)
+#define PS2_FSTS_RXOF		BIT(1)
+#define PS2_FSTS_RXRDY		BIT(0)
+
+
+#define PS2_LINE_ERROR_BIT \
+	(PS2_LSTS_TXTDO|PS2_LSTS_STOPERR|PS2_LSTS_ACKERR| \
+	PS2_LSTS_PARERR|PS2_LSTS_RXTDO)
+
+#define PS2_FIFO_ERROR_BIT \
+	(PS2_FSTS_TXUF|PS2_FSTS_TXOF|PS2_FSTS_TXRDY|PS2_FSTS_RXUF| \
+	PS2_FSTS_RXOF|PS2_FSTS_RXRDY)
+
+#define PS2_SAMPLE_CLK		(1000000)
+#define PS2_SCLK		(125000)
+
+struct sunxips2data {
+	struct serio *serio;
+	struct device *dev;
+
+	/* IO mapping base */
+	void __iomem	*reg_base;
+
+	/* clock management */
+	struct clk	*clk;
+
+	/* irq */
+	spinlock_t	lock;
+	int		irq;
+};
+
+/*********************/
+/* Interrupt handler */
+/*********************/
+static irqreturn_t sunxips2_interrupt(int irq, void *dev_id)
+{
+	struct sunxips2data *drvdata = dev_id;
+	u32 intr_status;
+	u32 fifo_status;
+	unsigned char byte;
+	u32 rval;
+	u32 error = 0;
+
+	spin_lock(&drvdata->lock);
+
+	/* Get the PS/2 interrupts and clear them */
+	intr_status  = readl(drvdata->reg_base + PS2_REG_LSTS);
+	fifo_status  = readl(drvdata->reg_base + PS2_REG_FSTS);
+
+	/*Check Line Status Register*/
+	if (intr_status & 0x10f) {
+		if (intr_status & PS2_LSTS_STOPERR)
+			dev_info(drvdata->dev, "PS/2 Stop Bit Error!");
+		if (intr_status & PS2_LSTS_ACKERR)
+			dev_info(drvdata->dev, "PS/2 Acknowledge Error!\n");
+		if (intr_status & PS2_LSTS_PARERR)
+			dev_info(drvdata->dev, "PS/2 Parity Error!\n");
+		if (intr_status & PS2_LSTS_TXTDO)
+			dev_info(drvdata->dev, "PS/2 Transmit Data Timeout!\n");
+		if (intr_status & PS2_LSTS_RXTDO)
+			dev_info(drvdata->dev, "PS/2 Receive Data Timeout!\n");
+
+		/*reset PS/2 controller*/
+		writel(readl(drvdata->reg_base + PS2_REG_GCTL) | PS2_GCTL_RESET,
+			drvdata->reg_base + PS2_REG_GCTL);
+
+		rval = PS2_LSTS_TXTDO | PS2_LSTS_STOPERR | PS2_LSTS_ACKERR |
+			PS2_LSTS_PARERR | PS2_LSTS_RXTDO;
+		writel(rval, drvdata->reg_base + PS2_REG_LSTS);
+		error = 1;
+	}
+
+	/*Check FIFO Status Register*/
+	if (fifo_status & 0x0606) {
+		if (fifo_status & PS2_FSTS_TXUF)
+			dev_info(drvdata->dev, "PS/2 Tx FIFO Underflow!\n");
+		if (fifo_status & PS2_FSTS_TXOF)
+			dev_info(drvdata->dev, "PS/2 Tx FIFO Overflow!\n");
+		if (fifo_status & PS2_FSTS_RXUF)
+			dev_info(drvdata->dev, "PS/2 Rx FIFO Underflow!\n");
+		if (fifo_status & PS2_FSTS_RXOF)
+			dev_info(drvdata->dev, "PS/2 Rx FIFO Overflow!\n");
+		/*reset PS/2 controller*/
+		writel(readl(drvdata->reg_base + PS2_REG_GCTL) | PS2_GCTL_RESET,
+			drvdata->reg_base + PS2_REG_GCTL);
+
+		rval = PS2_FSTS_TXUF | PS2_FSTS_TXOF | PS2_FSTS_TXRDY |
+			PS2_FSTS_RXUF | PS2_FSTS_RXOF | PS2_FSTS_RXRDY;
+		writel(rval, drvdata->reg_base + PS2_REG_FSTS);
+		error = 1;
+	}
+
+	rval = (fifo_status >> 16) & 0x3;
+	while (!error && rval--) {
+		byte = readl(drvdata->reg_base + PS2_REG_DATA) & 0xff;
+		/* dev_info(drvdata->dev, "PS/2 Receive %02x\n", byte); */
+		serio_interrupt(drvdata->serio, byte, 0);
+	}
+
+	writel(intr_status, drvdata->reg_base + PS2_REG_LSTS);
+	writel(fifo_status, drvdata->reg_base + PS2_REG_FSTS);
+
+	spin_unlock(&drvdata->lock);
+
+	return IRQ_HANDLED;
+}
+
+
+static int sunxips2_open(struct serio *pserio)
+{
+	struct sunxips2data *drvdata = pserio->port_data;
+	u32 src_clk = 0;
+	u32 clk_scdf;
+	u32 clk_pcdf;
+	u32 rval;
+
+	/*Set Line Control And Enable Interrupt*/
+	rval = PS2_LCTL_TXDTOEN | PS2_LCTL_STOPERREN | PS2_LCTL_ACKERREN
+		| PS2_LCTL_PARERREN | PS2_LCTL_RXDTOEN;
+	writel(rval, drvdata->reg_base + PS2_REG_LCTL);
+
+	/*Reset FIFO*/
+	rval = PS2_FCTL_TXRST|PS2_FCTL_RXRST|PS2_FCTL_TXUFIEN|PS2_FCTL_TXOFIEN
+		|PS2_FCTL_RXUFIEN|PS2_FCTL_RXOFIEN|PS2_FCTL_RXRDYIEN;
+	writel(rval, drvdata->reg_base + PS2_REG_FCTL);
+
+	src_clk = clk_get_rate(drvdata->clk);
+
+	if (!src_clk) {
+		dev_info(drvdata->dev, "w_ps2c_set_sclk error, source clock is 0.");
+		return -1;
+	}
+
+	/*Set Clock Divider Register*/
+	clk_scdf = DIV_ROUND_UP(src_clk, PS2_SAMPLE_CLK) - 1;
+	clk_pcdf = DIV_ROUND_UP(PS2_SAMPLE_CLK, PS2_SCLK) - 1;
+	rval = (clk_scdf<<8) | clk_pcdf;
+	writel(rval, drvdata->reg_base + PS2_REG_CLKDR);
+
+	/*Set Global Control Register*/
+	rval = PS2_GCTL_RESET | PS2_GCTL_INTEN | PS2_GCTL_MASTER
+		| PS2_GCTL_BUSEN;
+	writel(rval, drvdata->reg_base + PS2_REG_GCTL);
+
+	return 0;
+}
+
+static void sunxips2_close(struct serio *pserio)
+{
+	struct sunxips2data *drvdata = pserio->port_data;
+	unsigned long flags;
+
+	spin_lock_irqsave(&drvdata->lock, flags);
+	/* Disable the PS2 interrupts */
+	writel(0, drvdata->reg_base + PS2_REG_GCTL);
+	spin_unlock_irqrestore(&drvdata->lock, flags);
+}
+
+static int sunxips2_write(struct serio *pserio, unsigned char val)
+{
+	unsigned long expire = jiffies + msecs_to_jiffies(10000);
+	struct sunxips2data *drvdata = (struct sunxips2data *)pserio->port_data;
+
+	do {
+		if (readl(drvdata->reg_base + PS2_REG_FSTS) & PS2_FSTS_TXRDY) {
+			writel(val, drvdata->reg_base + PS2_REG_DATA);
+			return 0;
+		}
+	} while (time_before(jiffies, expire));
+
+	return 0;
+}
+
+static int sunxips2_probe(struct platform_device *pdev)
+{
+	struct resource *res; /* IO mem resources */
+	struct sunxips2data *drvdata;
+	struct serio *serio;
+	struct device *dev = &pdev->dev;
+	unsigned int irq;
+	int error;
+
+	drvdata = devm_kzalloc(dev, sizeof(struct sunxips2data), GFP_KERNEL);
+	serio = kzalloc(sizeof(struct serio), GFP_KERNEL);
+	if (!drvdata || !serio) {
+		error = -ENOMEM;
+		goto err_free_mem;
+	}
+
+	spin_lock_init(&drvdata->lock);
+
+	/* IO */
+	res = platform_get_resource(pdev, IORESOURCE_MEM, 0);
+	drvdata->reg_base = devm_ioremap_resource(dev, res);
+	if (IS_ERR(drvdata->reg_base)) {
+		dev_err(dev, "failed to map registers\n");
+		error = PTR_ERR(drvdata->reg_base);
+		goto err_free_mem;
+	}
+
+	drvdata->clk = devm_clk_get(dev, NULL);
+	if (!IS_ERR(drvdata->clk)) {
+		error = clk_prepare_enable(drvdata->clk);
+		if (error < 0) {
+			dev_err(dev, "failed to enable clock %d\n", error);
+			goto err_free_mem;
+		}
+	} else {
+		error = PTR_ERR(drvdata->clk);
+		dev_err(dev, "couldn't get clock %d\n", error);
+		goto err_free_mem;
+	}
+
+	serio->id.type = SERIO_8042;
+	serio->write = sunxips2_write;
+	serio->open = sunxips2_open;
+	serio->close = sunxips2_close;
+	serio->port_data = drvdata;
+	serio->dev.parent = dev;
+	strlcpy(serio->name, dev_name(dev), sizeof(serio->name));
+	strlcpy(serio->phys, dev_name(dev), sizeof(serio->phys));
+
+	/* Get IRQ for the device */
+	irq = platform_get_irq(pdev, 0);
+	if (!irq) {
+		dev_err(dev, "no IRQ found\n");
+		error = -ENXIO;
+		goto error_disable_clk;
+	}
+
+	drvdata->irq = irq;
+	drvdata->serio = serio;
+	drvdata->dev = dev;
+	error = devm_request_threaded_irq(dev, drvdata->irq,
+		sunxips2_interrupt, NULL, 0, DRIVER_NAME, drvdata);
+
+	if (error) {
+		dev_err(drvdata->dev, "Interrupt alloc failed %d:error:%d\n",
+			drvdata->irq, error);
+		goto error_disable_clk;
+	}
+
+	serio_register_port(serio);
+	platform_set_drvdata(pdev, drvdata);
+
+	return 0;	/* success */
+
+error_disable_clk:
+	clk_disable_unprepare(drvdata->clk);
+
+err_free_mem:
+	kfree(serio);
+	return error;
+}
+
+static int sunxips2_remove(struct platform_device *pdev)
+{
+	struct sunxips2data *drvdata = platform_get_drvdata(pdev);
+
+	serio_unregister_port(drvdata->serio);
+	disable_irq(drvdata->irq);
+
+	if (!IS_ERR(drvdata->clk))
+		clk_disable_unprepare(drvdata->clk);
+	kfree(drvdata->serio);
+
+	return 0;
+}
+
+/* Match table for of_platform binding */
+static const struct of_device_id sunxips2_of_match[] = {
+	{ .compatible = "allwinner,sun7i-a20-ps2", },
+	{ .compatible = "allwinner,sun4i-a10-ps2", },
+	{ },
+};
+
+MODULE_DEVICE_TABLE(of, sunxips2_of_match);
+
+/*platform driver structure*/
+static struct platform_driver sunxips2_of_driver = {
+	.probe		= sunxips2_probe,
+	.remove		= sunxips2_remove,
+	.driver = {
+		.name = DRIVER_NAME,
+		.of_match_table = sunxips2_of_match,
+	},
+};
+module_platform_driver(sunxips2_of_driver);
+
+MODULE_AUTHOR("Vishnu Patekar <vishnupatekar0510@gmail.com>");
+MODULE_AUTHOR("Aaron.maoye <leafy.myeh@newbietech.com>");
+MODULE_DESCRIPTION("Sunxi PS/2 driver");
+MODULE_LICENSE("GPL");