[patch 1/1] TOUCHSCREEN: S3C24XX touchscreen driver from Arnaud Patard.
Ben Dooks
ben at simtec.co.uk
Thu Nov 19 06:34:40 EST 2009
Dmitry Torokhov wrote:
> Hi Ben,
>
> On Wed, Nov 18, 2009 at 11:29:40PM +0000, Ben Dooks wrote:
>> From: Arnaud Patard <arnaud.patard at rtp-net.org>
>>
>> S3C24XX touchscreen driver, originally written by Arnaud Patard and
>> other contributors. This driver is the version from the Simtec Electronics
>> tree, and as such is the best place to start and thus proposed to be
>> merged into the linux input system.
>>
>
> Thank you for the patch. First thing first - do we have an agreement
> from all Samsung folks and other interested parties that _this_ is the
> driver? Because it's like 3rd implementation that came across...
I belive this is the best of the current driver bases, and hopefully
after this round of tidying will definitely be the best.
>> The driver has had substantial testing as well as a number of tidying
>> up passes done by Ben Dooks, as noted:
>>
>> - added kernel-doc comments to most of the routines
>> - removed old code from pre adc framework days
>> - updated device probe code to use platform id list matching
>> - cleaned up debug, since printk() now has timestamp feature
>> - ensure code uses dev_() reporting macros where necessary
>>
>> Signed-off-by: Arnaud Patard <arnaud.patard at rtp-net.org>
>> Signed-off-by: Simtec Linux Team <linux at simtec.co.uk>
>> Signed-off-by: Ben Dooks <ben at simtec.co.uk>
>>
>> ---
>> drivers/input/touchscreen/Kconfig | 18 +
>> drivers/input/touchscreen/Makefile | 1
>> drivers/input/touchscreen/s3c2410_ts.c | 464 +++++++++++++++++++++++++++++++++
>> 3 files changed, 483 insertions(+)
>>
>>
>> Index: b/drivers/input/touchscreen/Kconfig
>> ===================================================================
>> --- a/drivers/input/touchscreen/Kconfig 2009-11-09 22:28:23.000000000 +0000
>> +++ b/drivers/input/touchscreen/Kconfig 2009-11-10 10:38:44.000000000 +0000
>> @@ -133,6 +133,24 @@ config TOUCHSCREEN_FUJITSU
>> To compile this driver as a module, choose M here: the
>> module will be called fujitsu-ts.
>>
>> +config TOUCHSCREEN_S3C2410
>> + tristate "Samsung S3C2410 touchscreen input driver"
>> + depends on ARCH_S3C2410 && INPUT && INPUT_TOUCHSCREEN
>
> INPUT && INPUT_TOUCHSCREEN are superfluous.
ok, removed
>> + select SERIO
removed
> I don't think you need SERIO
>
>> + help
>> + Say Y here if you have the s3c2410 touchscreen.
>> +
>> + If unsure, say N.
>> +
>> + To compile this driver as a module, choose M here: the
>> + module will be called s3c2410_ts.
>> +
>> +config TOUCHSCREEN_S3C2410_DEBUG
>> + boolean "Samsung S3C2410 touchscreen debug messages"
>> + depends on TOUCHSCREEN_S3C2410
>> + help
>> + Select this if you want debug messages
>
> Where is this used?
thought it was used to define DEBUG in the driver, will look
at removing this.
>> +
>> config TOUCHSCREEN_GUNZE
>> tristate "Gunze AHL-51S touchscreen"
>> select SERIO
>> Index: b/drivers/input/touchscreen/Makefile
>> ===================================================================
>> --- a/drivers/input/touchscreen/Makefile 2009-11-09 22:28:23.000000000 +0000
>> +++ b/drivers/input/touchscreen/Makefile 2009-11-10 10:38:44.000000000 +0000
>> @@ -26,6 +26,7 @@ obj-$(CONFIG_TOUCHSCREEN_HP7XX) += jorn
>> obj-$(CONFIG_TOUCHSCREEN_HTCPEN) += htcpen.o
>> obj-$(CONFIG_TOUCHSCREEN_USB_COMPOSITE) += usbtouchscreen.o
>> obj-$(CONFIG_TOUCHSCREEN_PENMOUNT) += penmount.o
>> +obj-$(CONFIG_TOUCHSCREEN_S3C2410) += s3c2410_ts.o
>> obj-$(CONFIG_TOUCHSCREEN_TOUCHIT213) += touchit213.o
>> obj-$(CONFIG_TOUCHSCREEN_TOUCHRIGHT) += touchright.o
>> obj-$(CONFIG_TOUCHSCREEN_TOUCHWIN) += touchwin.o
>> Index: b/drivers/input/touchscreen/s3c2410_ts.c
>> ===================================================================
>> --- /dev/null 1970-01-01 00:00:00.000000000 +0000
>> +++ b/drivers/input/touchscreen/s3c2410_ts.c 2009-11-10 10:47:38.000000000 +0000
>> @@ -0,0 +1,464 @@
>> +/* drivers/input/touchscreen/s3c2410_ts.c
>> + *
>> + * Samsung S3C24XX touchscreen driver
>> + *
>> + * This program is free software; you can redistribute it and/or modify
>> + * it under the term 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.
>> + *
>> + * This program is distributed in the hope that it will be useful,
>> + * but WITHOUT ANY WARRANTY; without even the implied warranty of
>> + * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the
>> + * GNU General Public License for more details.
>> + *
>> + * You should have received a copy of the GNU General Public License
>> + * along with this program; if not, write to the Free Software
>> + * Foundation, Inc., 59 Temple Place, Suite 330, Boston, MA 02111-1307 USA
>> + *
>> + * Copyright 2004 Arnaud Patard <arnaud.patard at rtp-net.org>
>> + * Copyright 2008 Ben Dooks <ben-linux at fluff.org>
>> + * Copyright 2009 Simtec Electronics <linux at simtec.co.uk>
>> + *
>> + * Additional work by Herbert Pötzl <herbert at 13thfloor.at> and
>> + * Harald Welte <laforge at openmoko.org>
>> + */
>> +
>> +#include <linux/errno.h>
>> +#include <linux/kernel.h>
>> +#include <linux/module.h>
>> +#include <linux/slab.h>
>> +#include <linux/gpio.h>
>> +#include <linux/input.h>
>> +#include <linux/init.h>
>> +#include <linux/serio.h>
>
> No serio in sight.
thanks, removed.
>> +#include <linux/delay.h>
>> +#include <linux/interrupt.h>
>> +#include <linux/platform_device.h>
>> +#include <linux/clk.h>
>> +#include <linux/io.h>
>> +
>> +#include <plat/adc.h>
>> +#include <plat/regs-adc.h>
>> +
>> +#include <mach/regs-gpio.h>
>> +#include <mach/ts.h>
>> +
>> +/* For ts.dev.id.version */
>> +#define S3C2410TSVERSION 0x0101
>> +
>> +#define TSC_SLEEP (S3C2410_ADCTSC_PULL_UP_DISABLE | S3C2410_ADCTSC_XY_PST(0))
>> +
>> +#define INT_DOWN (0)
>> +#define INT_UP (1 << 8)
>> +
>> +#define WAIT4INT (S3C2410_ADCTSC_YM_SEN | \
>> + S3C2410_ADCTSC_YP_SEN | \
>> + S3C2410_ADCTSC_XP_SEN | \
>> + S3C2410_ADCTSC_XY_PST(3))
>> +
>> +#define AUTOPST (S3C2410_ADCTSC_YM_SEN | \
>> + S3C2410_ADCTSC_YP_SEN | \
>> + S3C2410_ADCTSC_XP_SEN | \
>> + S3C2410_ADCTSC_AUTO_PST | \
>> + S3C2410_ADCTSC_XY_PST(0))
>> +
>> +#define DEBUG_LVL KERN_DEBUG
>
> Don't seem to be used.
thanks, removed.
>> +
>> +static char *s3c2410ts_name = "s3c2410 TouchScreen";
>> +
>> +/* Per-touchscreen data. */
>> +
>> +/**
>> + * struct s3c2410ts - driver touchscreen state.
>> + * @client: The ADC client we registered with the core driver.
>> + * @dev: The device we are bound to.
>> + * @input: The input device we registered with the input subsystem.
>> + * @clock: The clock for the adc.
>> + * @io: Pointer to the IO base.
>> + * @xp: The accumulated X position data.
>> + * @yp: The accumulated Y position data.
>> + * @irq_tc: The interrupt number for pen up/down interrupt
>> + * @count: The number of samples collected.
>> + * @shift: The log2 of the maximum count to read in one go.
>> + */
>
> These sructures are driver-internal and so don't need to be kernel-doc-ed.
> Same goes for the driver-private functions.
I like having the documentation, and I would much prefer to leave it
in as useful.
>> +struct s3c2410ts {
>> + struct s3c_adc_client *client;
>> + struct device *dev;
>> + struct input_dev *input;
>> + struct clk *clock;
>> + void __iomem *io;
>> + unsigned long xp;
>> + unsigned long yp;
>> + int irq_tc;
>> + int count;
>> + int shift;
>> +};
>> +
>> +static struct s3c2410ts ts;
>> +
>> +/**
>> + * s3c2410_ts_connect - configure gpio for s3c2410 systems
>> + *
>> + * Configure the GPIO for the S3C2410 system, where we have external FETs
>> + * connected to the device (later systems such as the S3C2440 integrate
>> + * these into the device).
>> +*/
>> +static inline void s3c2410_ts_connect(void)
>> +{
>> + s3c2410_gpio_cfgpin(S3C2410_GPG(12), S3C2410_GPG12_XMON);
>> + s3c2410_gpio_cfgpin(S3C2410_GPG(13), S3C2410_GPG13_nXPON);
>> + s3c2410_gpio_cfgpin(S3C2410_GPG(14), S3C2410_GPG14_YMON);
>> + s3c2410_gpio_cfgpin(S3C2410_GPG(15), S3C2410_GPG15_nYPON);
>
> No gpiolib? Also, should it be in the driver or maybe in the platform
> code?
gpiolib doesn't deal with pin function configuration past input
or output. All these gpios need to be in their special-function
mode.
If people really object, this can be removed and the machine
support files changed.
>> +}
>> +
>> +/**
>> + * get_down - return the down state of the pen
>> + * @data0: The data read from ADCDAT0 register.
>> + * @data1: The data read from ADCDAT1 register.
>> + *
>> + * Return non-zero if both readings show that the pen is down.
>> + */
>> +static inline int get_down(unsigned long data0, unsigned long data1)
>
> bool?
thanks, fixed.
>> +{
>> + /* returns true if both data values show stylus down */
>> + return (!(data0 & S3C2410_ADCDAT0_UPDOWN) &&
>> + !(data1 & S3C2410_ADCDAT0_UPDOWN));
>> +}
>> +
>> +static void touch_timer_fire(unsigned long data)
>> +{
>> + unsigned long data0;
>> + unsigned long data1;
>> + int down;
>
> bool?
thanks, fixed.
>> +
>> + data0 = readl(ts.io + S3C2410_ADCDAT0);
>> + data1 = readl(ts.io + S3C2410_ADCDAT1);
>> +
>> + down = get_down(data0, data1);
>> +
>> + if (ts.count == (1<<ts.shift)) {
>
> Syyle: x << y
thanks, fixed.
>> + ts.xp >>= ts.shift;
>> + ts.yp >>= ts.shift;
>> +
>> + dev_dbg(ts.dev, "%s: X=%lu, Y=%lu, count=%d\n",
>> + __func__, ts.xp, ts.yp, ts.count);
>> +
>> + input_report_abs(ts.input, ABS_X, ts.xp);
>> + input_report_abs(ts.input, ABS_Y, ts.yp);
>> +
>> + input_report_key(ts.input, BTN_TOUCH, 1);
>> + input_report_abs(ts.input, ABS_PRESSURE, 1);
>
> No fake pressure events please, BTN_TOUCH should be enough.
I'd have to check, IIRC tslib needs these to function properly.
>> + input_sync(ts.input);
>> +
>> + ts.xp = 0;
>> + ts.yp = 0;
>> + ts.count = 0;
>> + }
>> +
>> + if (down) {
>> + s3c_adc_start(ts.client, 0, 1 << ts.shift);
>> + } else {
>> + ts.count = 0;
>> +
>> + input_report_key(ts.input, BTN_TOUCH, 0);
>> + input_report_abs(ts.input, ABS_PRESSURE, 0);
>> + input_sync(ts.input);
>> +
>> + writel(WAIT4INT | INT_DOWN, ts.io + S3C2410_ADCTSC);
>> + }
>> +}
>> +
>> +static struct timer_list touch_timer = TIMER_INITIALIZER(touch_timer_fire, 0, 0);
>
> static DEFINE_TIMER(...);
ok, thanks.
>> +
>> +/**
>> + * stylus_irq - touchscreen stylus event interrupt
>> + * @irq: The interrupt number
>> + * @dev_id: The device ID.
>> + *
>> + * Called when the IRQ_TC is fired for a pen up or down event.
>> + */
>> +static irqreturn_t stylus_irq(int irq, void *dev_id)
>> +{
>> + unsigned long data0;
>> + unsigned long data1;
>> + int down;
>> +
>> + data0 = readl(ts.io + S3C2410_ADCDAT0);
>> + data1 = readl(ts.io + S3C2410_ADCDAT1);
>> +
>> + down = get_down(data0, data1);
>> +
>> + /* TODO we should never get an interrupt with down set while
>> + * the timer is running, but maybe we ought to verify that the
>> + * timer isn't running anyways. */
>> +
>> + if (down)
>> + s3c_adc_start(ts.client, 0, 1 << ts.shift);
>> + else
>> + dev_info(ts.dev, "%s: count=%d\n", __func__, ts.count);
>> +
>> + return IRQ_HANDLED;
>> +}
>> +
>> +/**
>> + * s3c24xx_ts_conversion - ADC conversion callback
>> + * @client: The client that was registered with the ADC core.
>> + * @data0: The reading from ADCDAT0.
>> + * @data1: The reading from ADCDAT1.
>> + * @left: The number of samples left.
>> + *
>> + * Called when a conversion has finished.
>> + */
>> +static void s3c24xx_ts_conversion(struct s3c_adc_client *client,
>> + unsigned data0, unsigned data1,
>> + unsigned *left)
>> +{
>> + dev_dbg(ts.dev, "%s: %d,%d\n", __func__, data0, data1);
>> +
>> + ts.xp += data0;
>> + ts.yp += data1;
>> +
>> + ts.count++;
>> +
>> + /* From tests, it seems that it is unlikely to get a pen-up
>> + * event during the conversion process which means we can
>> + * ignore any pen-up events with less than the requisite
>> + * count done.
>> + *
>> + * In several thousand conversions, no pen-ups where detected
>> + * before count completed.
>> + */
>> +}
>> +
>> +/**
>> + * s3c24xx_ts_select - ADC selection callback.
>> + * @client: The client that was registered with the ADC core.
>> + * @select: The reason for select.
>> + *
>> + * Called when the ADC core selects (or deslects) us as a client.
>> + */
>> +static void s3c24xx_ts_select(struct s3c_adc_client *client, unsigned select)
>> +{
>> + if (select) {
>> + writel(S3C2410_ADCTSC_PULL_UP_DISABLE | AUTOPST,
>> + ts.io + S3C2410_ADCTSC);
>> + } else {
>> + mod_timer(&touch_timer, jiffies+1);
>> + writel(WAIT4INT | INT_UP, ts.io + S3C2410_ADCTSC);
>> + }
>> +}
>> +
>> +/**
>> + * s3c2410ts_probe - device core probe entry point
>> + * @pdev: The device we are being bound to.
>> + *
>> + * Initialise, find and allocate any resources we need to run and then
>> + * register with the ADC and input systems.
>> + */
>> +static int __init s3c2410ts_probe(struct platform_device *pdev)
>
> __devinit or switch to platform_driver_probe().
thanks, fixed.
>> +{
>> + struct s3c2410_ts_mach_info *info;
>> + struct device *dev = &pdev->dev;
>> + struct input_dev *input_dev;
>> + struct resource *res;
>> + int ret = -EINVAL;
>
> Can we call it "error" (since that's what you use it for).
Is it really necessary to change this?
>> +
>> + /* Initialise input stuff */
>> + memset(&ts, 0, sizeof(struct s3c2410ts));
>> +
>> + ts.dev = dev;
>> +
>> + info = pdev->dev.platform_data;
>> + if (!info) {
>> + dev_err(dev, "no platform data, cannot attach\n");
>> + return -EINVAL;
>> + }
>> +
>> + dev_dbg(dev, "initialising touchscreen\n");
>> +
>> + ts.clock = clk_get(dev, "adc");
>> + if (IS_ERR(ts.clock)) {
>> + dev_err(dev, "cannot get adc clock source\n");
>> + return -ENOENT;
>> + }
>> +
>> + clk_enable(ts.clock);
>> + dev_dbg(dev, "got and enabled clocks\n");
>> +
>> + ts.irq_tc = ret = platform_get_irq(pdev, 0);
>> + if (ret < 0) {
>> + dev_err(dev, "no resource for interrupt\n");
>> + goto err_clk;
>> + }
>> +
>> + res = platform_get_resource(pdev, IORESOURCE_MEM, 0);
>> + if (!res) {
>> + dev_err(dev, "no resource for registers\n");
>> + ret = -ENOENT;
>> + goto err_clk;
>> + }
>> +
>
> request_mem_region() here?
I'll check if it possible for both the adc and this driver
to claim this region.
>> + ts.io = ioremap(res->start, resource_size(res));
>> + if (ts.io == NULL) {
>> + dev_err(dev, "cannot map registers\n");
>> + ret = -ENOMEM;
>> + goto err_clk;
>> + }
>> +
>> + /* Configure the touchscreen external FETs on the S3C2410 */
>> + if (!platform_get_device_id(pdev)->driver_data)
>> + s3c2410_ts_connect();
>> +
>> + ts.client = s3c_adc_register(pdev, s3c24xx_ts_select,
>> + s3c24xx_ts_conversion, 1);
>> + if (IS_ERR(ts.client)) {
>> + dev_err(dev, "failed to register adc client\n");
>> + ret = PTR_ERR(ts.client);
>> + goto err_iomap;
>> + }
>> +
>> + /* Initialise registers */
>> + if ((info->delay & 0xffff) > 0)
>> + writel(info->delay & 0xffff, ts.io + S3C2410_ADCDLY);
>> +
>> + writel(WAIT4INT | INT_DOWN, ts.io + S3C2410_ADCTSC);
>> +
>> + input_dev = input_allocate_device();
>> + if (!input_dev) {
>> + dev_err(dev, "Unable to allocate the input device !!\n");
>> + ret = -ENOMEM;
>> + goto err_iomap;
>> + }
>> +
>> + ts.input = input_dev;
>> + ts.input->evbit[0] = BIT_MASK(EV_SYN) | BIT_MASK(EV_KEY) | BIT_MASK(EV_ABS);
>
> No need setting EV_SYN explicitely.
ok, fixed.
>> + ts.input->keybit[BIT_WORD(BTN_TOUCH)] = BIT_MASK(BTN_TOUCH);
>> + input_set_abs_params(ts.input, ABS_X, 0, 0x3FF, 0, 0);
>> + input_set_abs_params(ts.input, ABS_Y, 0, 0x3FF, 0, 0);
>> + input_set_abs_params(ts.input, ABS_PRESSURE, 0, 1, 0, 0);
>
> Drop ABS_PRESSURE.
ok, see above.
>> +
>> + ts.input->name = s3c2410ts_name;
>> + ts.input->id.bustype = BUS_HOST;
>> + ts.input->id.vendor = 0xDEAD;
>> + ts.input->id.product = 0xBEEF;
>> + ts.input->id.version = S3C2410TSVERSION;
>> +
>> + ts.shift = info->oversampling_shift;
>> +
>> + if (request_irq(ts.irq_tc, stylus_irq, IRQF_DISABLED,
>> + "s3c2410_ts_pen", ts.input)) {
>> + dev_err(dev, "cannot get TC interrupt\n");
>> + ret = -EIO;
>
> Don't mangle what request_irq returned.
ok, fixed.
>> + goto err_inputdev;
>> + }
>> +
>> + dev_info(dev, "driver attached, registering input device\n");
>> +
>> + /* All went ok, so register to the input system */
>> + ret = input_register_device(ts.input);
>> + if (ret < 0) {
>> + dev_err(dev, "failed to register input device\n");
>> + ret = -EIO;
>> + goto err_tcirq;
>> + }
>> +
>> + return 0;
>> +
>> + err_tcirq:
>> + free_irq(ts.irq_tc, ts.input);
>
> del_timer_sync().
added.
>> + err_inputdev:
>> + input_unregister_device(ts.input);
>> + err_iomap:
>> + iounmap(ts.io);
>> + err_clk:
>> + clk_put(ts.clock);
>> + return ret;
>> +}
>> +
>> +/**
>> + * s3c2410ts_remove - device core removal entry point
>> + * @pdev: The device we are being removed from.
>> + *
>> + * Free up our state ready to be removed.
>> + */
>> +static int s3c2410ts_remove(struct platform_device *pdev)
>> +{
>> + free_irq(ts.irq_tc, ts.input);
>
> del_timer_sync().
added, thanks.
>> +
>> + clk_disable(ts.clock);
>> + clk_put(ts.clock);
>> +
>> + input_unregister_device(ts.input);
>> + iounmap(ts.io);
>
> release_mem_region()
see above.
>> +
>> + return 0;
>> +}
>> +
>> +#ifdef CONFIG_PM
>> +static int s3c2410ts_suspend(struct platform_device *pdev, pm_message_t state)
>> +{
>> + writel(TSC_SLEEP, ts.io + S3C2410_ADCTSC);
>> + disable_irq(ts.irq_tc);
>> + clk_disable(ts.clock);
>> +
>> + return 0;
>> +}
>> +
>> +static int s3c2410ts_resume(struct platform_device *pdev)
>> +{
>> + struct s3c2410_ts_mach_info *info = pdev->dev.platform_data;
>> +
>> + clk_enable(ts.clock);
>> +
>> + /* Initialise registers */
>> + if ((info->delay & 0xffff) > 0)
>> + writel(info->delay & 0xffff, ts.io + S3C2410_ADCDLY);
>> +
>> + writel(WAIT4INT | INT_DOWN, ts.io + S3C2410_ADCTSC);
>> +
>> + return 0;
>> +}
>> +
>> +#else
>> +#define s3c2410ts_suspend NULL
>> +#define s3c2410ts_resume NULL
>> +#endif
>> +
>> +static struct platform_device_id s3cts_driver_ids[] = {
>> + { "s3c2410-ts", 0 },
>> + { "s3c2440-ts", 1 },
>> + { }
>> +};
>> +MODULE_DEVICE_TABLE(platform, s3cts_driver_ids);
>> +
>> +static struct platform_driver s3c_ts_driver = {
>> + .driver = {
>> + .name = "s3c24xx-ts",
>> + .owner = THIS_MODULE,
>> + },
>> + .id_table = s3cts_driver_ids,
>> + .probe = s3c2410ts_probe,
>> + .remove = s3c2410ts_remove,
>
> __devexit_p()
>
>> + .suspend = s3c2410ts_suspend,
>> + .resume = s3c2410ts_resume,
>
> Switch to pm_ops.
ok, will do. may as well remove the #ifdef CONFIG_PM
for such small amount of code too.
>> +};
>> +
>> +static int __init s3c2410ts_init(void)
>> +{
>> + return platform_driver_register(&s3c_ts_driver);
>> +}
>> +
>> +static void __exit s3c2410ts_exit(void)
>> +{
>> + platform_driver_unregister(&s3c_ts_driver);
>> +}
>> +
>> +module_init(s3c2410ts_init);
>> +module_exit(s3c2410ts_exit);
>> +
>> +MODULE_AUTHOR("Arnaud Patard <arnaud.patard at rtp-net.org>, "
>> + "Ben Dooks <ben at simtec.co.uk>, "
>> + "Simtec Electronics <linux at simtec.co.uk>");
>> +MODULE_DESCRIPTION("S3C24XX Touchscreen driver");
>> +MODULE_LICENSE("GPL v2");
>>
>
> Thanks!
I'll try and work on the to-do items and do another round
of testing before the weekend.
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