[PATCH] input/touchscreen: add S3C24XX SoC touchscreen input driver
Dmitry Torokhov
dmitry.torokhov at gmail.com
Mon Oct 19 21:38:37 EDT 2009
Hi Shine,
On Mon, Oct 19, 2009 at 06:54:21PM +0800, Shine Liu wrote:
>
> This touchscreen driver is for touchscreen controller on Samsung
> S3C2410/S3C2440 SoC chip. S3C2410/S3C2440 has the on chip touchscreen
> controller based on it's analog to digital converter(8-channel analog
> inputs, touchscreen uses 4 of them). This driver uses the exsiting S3C
> ADC driver to make the touchscreen controller of S3C2410/S3C2440 work
> well together with other ADC devices connected to the S3C24XX SoC chip.
>
> The patch is created against kernel 2.6.32-rc4 and tested with S3C2440
> SoC and Samsung LTE430WQ-F0C touchscreen.
So I understand there are questions whether this verson of driver should
be merged, I'll let you guys workit it out. I think that filtering is
better be left off to tslib since there are many more opportunities to
do this kind of stuff in userspace.
Still, below some comments so that the next iteration of the driver does
not have the same faults ;)
>
> Signed-off-by: Shine Liu <liuxian at redflag-linux.com>
> Signed-off-by: Shine Liu <shinel at foxmail.com>
Umm, is it the same person? Then one sign-off is enough ;)
> --------------------------------------------------------
>
> --- a/drivers/input/touchscreen/Makefile 2009-10-12 05:43:56.000000000 +0800
> +++ b/drivers/input/touchscreen/Makefile 2009-10-13 20:35:02.000000000 +0800
> @@ -10,6 +10,7 @@
> obj-$(CONFIG_TOUCHSCREEN_AD7879) += ad7879.o
> obj-$(CONFIG_TOUCHSCREEN_ADS7846) += ads7846.o
> obj-$(CONFIG_TOUCHSCREEN_ATMEL_TSADCC) += atmel_tsadcc.o
> +obj-$(CONFIG_TOUCHSCREEN_S3C24XX_TSADCC) += s3c24xx_tsadcc.o
> obj-$(CONFIG_TOUCHSCREEN_BITSY) += h3600_ts_input.o
> obj-$(CONFIG_TOUCHSCREEN_CORGI) += corgi_ts.o
> obj-$(CONFIG_TOUCHSCREEN_GUNZE) += gunze.o
> --- a/drivers/input/touchscreen/Kconfig 2009-10-12 05:43:56.000000000 +0800
> +++ b/drivers/input/touchscreen/Kconfig 2009-10-13 20:37:51.000000000 +0800
> @@ -307,6 +307,19 @@
> To compile this driver as a module, choose M here: the
> module will be called atmel_tsadcc.
>
> +config TOUCHSCREEN_S3C24XX_TSADCC
> + tristate "Samsung S3C24XX touchscreen input driver"
> + depends on ARCH_S3C2410 && S3C24XX_ADC && INPUT && INPUT_TOUCHSCREEN
> + select SERIO
Why do you need SERIO? I don't see it being a serio driver.
> + help
> + Say Y here if you have a touchscreen connected to the ADC Controller
> + on your s3c2410/s3c2440 SoC.
> +
> + If unsure, say N.
> +
> + To compile this driver as a module, choose M here: the
> + module will be called s3c24xx_tsadcc.
> +
> config TOUCHSCREEN_UCB1400
> tristate "Philips UCB1400 touchscreen"
> depends on AC97_BUS
> --- /dev/null 2009-10-09 10:57:12.360986601 +0800
> +++ b/drivers/input/touchscreen/s3c24xx_tsadcc.c 2009-10-19 17:16:57.000000000 +0800
> @@ -0,0 +1,432 @@
> +/*
> + * 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.
> + *
> + * 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
> + *
> + * Part of the code come from openmoko project.
> + *
> + * Shine Liu <shinel at foxmail.com>
> + */
> +
> +#include <linux/errno.h>
> +#include <linux/kernel.h>
> +#include <linux/module.h>
> +#include <linux/slab.h>
> +#include <linux/input.h>
> +#include <linux/init.h>
> +#include <linux/serio.h>
NO need to include this.
> +#include <linux/timer.h>
> +#include <linux/delay.h>
> +#include <linux/platform_device.h>
> +#include <linux/clk.h>
> +#include <linux/io.h>
> +#include <asm/irq.h>
> +
> +#include <mach/gpio.h>
> +#include <mach/regs-gpio.h>
> +#include <mach/hardware.h>
> +#include <plat/regs-adc.h>
> +#include <plat/adc.h>
> +
> +
> +MODULE_AUTHOR("Shine Liu <shinel at foxmail.com>");
> +MODULE_DESCRIPTION("Samsung s3c24xx touchscreen driver");
> +MODULE_LICENSE("GPL");
> +
> +
> +#define S3C24XX_TS_VERSION 0x0101
> +
> +#define TSC_SLEEP (S3C2410_ADCTSC_PULL_UP_DISABLE | \
> + S3C2410_ADCTSC_XY_PST(0))
> +
> +#define WAIT4INT(x) (((x)<<8) | \
> + S3C2410_ADCTSC_YM_SEN | \
> + S3C2410_ADCTSC_YP_SEN | \
> + S3C2410_ADCTSC_XP_SEN | \
> + S3C2410_ADCTSC_XY_PST(3))
> +
> +#define AUTO_XY (S3C2410_ADCTSC_PULL_UP_DISABLE | \
> + S3C2410_ADCTSC_AUTO_PST | \
> + S3C2410_ADCTSC_XY_PST(0))
> +
> +#define TS_STATE_STANDBY 0 /* initial state */
> +#define TS_STATE_PRESSED 1
> +#define TS_STATE_RELEASE_PENDING 2 /* wait to confirm the up event */
> +#define TS_STATE_RELEASE 3
> +
> +#define TIME_RELEASE_PENDING (HZ / 20) /* about 50ms */
> +#define TIME_NEXT_CONV ((HZ < 51)? 1 : HZ / 50) /* about 20ms */
> +
> +static char *s3c24xx_ts_name = "Samsung s3c24xx TouchScreen";
> +static void __iomem *base_addr;
No chance of a second device? I'd put it in s3c24xx_ts anyway.
> +
> +
> +/*
> + * Per-touchscreen data.
> + */
> +
> +struct s3c24xx_ts {
> + struct input_dev *dev;
> + struct s3c_adc_client *adc_client;
> + unsigned char is_down;
> + unsigned char state;
> + unsigned adc_selected;
> + unsigned int delay; /* register value for delay */
> + unsigned int presc; /* register value for prescaler */
> +};
> +
> +static struct s3c24xx_ts ts;
Better use platform_set_drvdata and platform_get_drvdata instead of a
global.
> +
> +
> +/*
> + * Low level functions to config registers.
> + */
> +static inline void s3c24xx_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);
> +}
> +
> +static void s3c24xx_ts_start_adc_conversion(void)
> +{
> + pr_debug("start_adc_conv ADCTSC: 0x%x",
> + readl(base_addr + S3C2410_ADCTSC));
> + writel(AUTO_XY, base_addr + S3C2410_ADCTSC);
> + pr_debug(" ---> 0x%x",
> + readl(base_addr + S3C2410_ADCTSC));
> + s3c_adc_start(ts.adc_client, 0, 1);
> + pr_debug(" ---> 0x%x\n",
> + readl(base_addr + S3C2410_ADCTSC));
> +}
> +
> +
> +/*
> + * Event handling
> + */
> +
> +enum ts_input_event {IE_UP = 0, IE_DOWN};
> +
> +static void ts_input_report(int event, int coords[])
> +{
> +
> + if (event == IE_DOWN) {
> + input_report_abs(ts.dev, ABS_X, coords[0]);
> + input_report_abs(ts.dev, ABS_Y, coords[1]);
> + input_report_key(ts.dev, BTN_TOUCH, 1);
> + input_report_abs(ts.dev, ABS_PRESSURE, 1);
No fake pressure events please.
> +
> + pr_debug("down (X:%03d, Y:%03d)\n", coords[0], coords[1]);
Maybe use dev_dbg()?
> + } else {
> + input_report_key(ts.dev, BTN_TOUCH, 0);
> + input_report_abs(ts.dev, ABS_PRESSURE, 0);
> + pr_debug("up\n");
> + }
> +
> + input_sync(ts.dev);
> +}
> +
> +
> +/*
> + * Timer to process the UP event or to report the postion of DRAG
> + */
> +
> +static void ts_drag_pull_timer_f(unsigned long data);
> +static struct timer_list ts_drag_pull_timer =
> + TIMER_INITIALIZER(ts_drag_pull_timer_f, 0, 0);
Move it to the device structure as well.
> +
> +static void ts_drag_pull_timer_f(unsigned long data)
> +{
> + unsigned long flags;
> + /* delay reporting the UP event to avoid jitter */
> + static unsigned release_pending_counter = 0;
> + pr_debug("Timer called: is_down[%d] status[%d]\n", ts.is_down, ts.state);
> +
> + local_irq_save(flags);
Is it really needed?
> + if(ts.state == TS_STATE_RELEASE_PENDING) {
> + if(release_pending_counter++ < 1) {
> + /* jitter avoidance window: delay TIME_RELEASE_PENDING jfs */
> + mod_timer(&ts_drag_pull_timer, jiffies + TIME_RELEASE_PENDING);
> + } else {
> + /* no down event occurd during last delay */
> + release_pending_counter = 0;
> + ts_input_report(IE_UP, NULL);
> + ts.state = TS_STATE_RELEASE;
> + writel(WAIT4INT(0), base_addr + S3C2410_ADCTSC);
> + }
> + local_irq_restore(flags);
> + return;
> + }
> +
> + /* ts.is_down should be true here */
> + s3c24xx_ts_start_adc_conversion();
> + local_irq_restore(flags);
> +}
> +
> +
> +/*
> + * ISR for the IRQ_TS
> + */
> +
> +static irqreturn_t stylus_updown(int irq, void *dev_id)
> +{
> + unsigned long data0;
> + unsigned long data1;
> + unsigned long adctsc;
> + int event_type; /* 1 for down, 0 for up */
> +
> + /*
> + * According to s3c2440 manual chap16: After Touch Screen
> + * Controller generates INT_TC, XY_PST must be set to [00]
> + */
> + adctsc = readl(base_addr + S3C2410_ADCTSC);
> + writel(adctsc & ~(S3C2410_ADCTSC_XY_PST(3)), base_addr + S3C2410_ADCTSC);
> + data0 = readl(base_addr + S3C2410_ADCDAT0);
> + data1 = readl(base_addr + S3C2410_ADCDAT1);
> + event_type = (!(data0 & S3C2410_ADCDAT0_UPDOWN)) &&
> + (!(data1 & S3C2410_ADCDAT0_UPDOWN));
> + pr_debug("event_type: %d, DATA0 0x%lx, DATA1 0x%lx, ADCTSC 0x%lx, "
> + "ADCUPDN 0x%x\n", event_type, data0, data1,
> + adctsc, readl(base_addr + 0x14));
> +
> + /* ignore sequential same event */
> + if(ts.is_down == event_type) {
> + pr_debug("###Ignore same event: %d\n", event_type);
> + /* restore XY_PST */
> + writel(adctsc, base_addr + S3C2410_ADCTSC);
> + return IRQ_HANDLED;
> + }
> +
> + ts.is_down = event_type;
> + if (ts.is_down) {
> + s3c24xx_ts_start_adc_conversion();
> + } else {
> + ts.state = TS_STATE_RELEASE_PENDING;
> + /*
> + * Delay to report the up event for a while to avoid jitter.
> + * This state will be checked after (0, TIME_NEXT_CONV)
> + * jiffies depended on when the interrupt occured.
> + */
> + }
> +
> + return IRQ_HANDLED;
> +}
> +
> +/*
> + * Called in ISR of IRQ_ADC
> + */
> +
> +static void stylus_adc_action(struct s3c_adc_client *client,
> + unsigned p0, unsigned p1, unsigned *conv_left)
> +{
> + int buf[2];
> + unsigned long flags;
> +
> + local_irq_save(flags);
Why?
> + /*
> + * IRQ_TS may rise just in the time window between AUTO_XY mode
> + * set and this pointer */
> + if(ts.state == TS_STATE_RELEASE_PENDING)
> + {
> + local_irq_restore(flags);
> + return;
> + }
> +
> + /* Grab the ADC results. */
> + buf[0] = p0;
> + buf[1] = p1;
> +
> + ts_input_report(IE_DOWN, buf);
> + pr_debug("[adc_selected: %d] ADCTSC: 0x%x",
> + ts.adc_selected, readl(base_addr + S3C2410_ADCTSC));
> +
> + writel(WAIT4INT(1), base_addr + S3C2410_ADCTSC);
> + printk(" ---> 0x%x\n",
> + readl(base_addr + S3C2410_ADCTSC));
> +
> + ts.state = TS_STATE_PRESSED;
> + mod_timer(&ts_drag_pull_timer, jiffies + TIME_NEXT_CONV);
> + local_irq_restore(flags);
> +}
> +
> +
> +/*
> + * callback function for s3c-adc
> + */
> +
> +void adc_selected_f(struct s3c_adc_client *client, unsigned selected)
> +{
> + ts.adc_selected = selected;
> +}
> +
> +
> +/*
> + * The functions for inserting/removing us as a module.
> + */
> +
> +static int __init s3c24xx_ts_probe(struct platform_device *pdev)
__devinit.
> +{
> + int rc;
> + struct input_dev *input_dev;
> + int ret = 0;
> +
> + dev_info(&pdev->dev, "Starting\n");
> + pr_debug("Entering s3c24xx_ts_probe\n");
> +
> + base_addr = ioremap(S3C2410_PA_ADC, 0x20);
> + if (base_addr == NULL) {
> + dev_err(&pdev->dev, "Failed to remap register block\n");
> + ret = -ENOMEM;
> + goto fail0;
> + }
> +
> + /* Configure GPIOs */
> + s3c24xx_ts_connect();
> +
> + writel(WAIT4INT(0), base_addr + S3C2410_ADCTSC);
> +
> + /* Initialise input stuff */
> + memset(&ts, 0, sizeof(struct s3c24xx_ts));
> + ts.adc_client =
> + s3c_adc_register(pdev, adc_selected_f, stylus_adc_action, 1);
> + if (!ts.adc_client) {
> + dev_err(&pdev->dev,
> + "Unable to register s3c24xx_ts as s3c_adc client\n");
> + ret = -EIO;
> + goto fail1;
-EWIERDIDENTATION.
> + }
> +
> + /* save prescale EN and VAL in the S3C2410_ADCCON register */
> + ts.presc = readl(base_addr + S3C2410_ADCCON);
> + /* save value of S3C2410_ADCDLY register */
> + ts.delay = readl(base_addr + S3C2410_ADCDLY);
> + pr_debug("platform data: ADCCON=%08x ADCDLY=%08x\n", ts.presc, ts.delay);
> +
> + input_dev = input_allocate_device();
> + if (!input_dev) {
> + dev_err(&pdev->dev, "Unable to allocate the input device\n");
> + ret = -ENOMEM;
> + goto fail2;
> + }
> +
> + ts.dev = input_dev;
> + ts.dev->evbit[0] = BIT_MASK(EV_SYN) | BIT_MASK(EV_KEY) | BIT_MASK(EV_ABS);
> + ts.dev->keybit[BIT_WORD(BTN_TOUCH)] = BIT_MASK(BTN_TOUCH);
> + input_set_abs_params(ts.dev, ABS_X, 0, 0x3FF, 0, 0);
> + input_set_abs_params(ts.dev, ABS_Y, 0, 0x3FF, 0, 0);
> + input_set_abs_params(ts.dev, ABS_PRESSURE, 0, 1, 0, 0);
Kill the above line.
> +
> + ts.dev->name = s3c24xx_ts_name;
> + ts.dev->id.bustype = BUS_RS232;
Really?
> + ts.dev->id.vendor = 0xBAAD;
> + ts.dev->id.product = 0xBEEF;
> + ts.dev->id.version = S3C24XX_TS_VERSION;
> + ts.state = TS_STATE_STANDBY;
> +
> + /* Get IRQ */
> + if (request_irq(IRQ_TC, stylus_updown, IRQF_SAMPLE_RANDOM,
> + "s3c24xx_ts_action", ts.dev)) {
> + dev_err(&pdev->dev, "Could not allocate ts IRQ_TC !\n");
> + ret = -EIO;
> + goto fail3;
> + }
> +
> + dev_info(&pdev->dev, "Successfully loaded\n");
No need.
> +
> + /* All went ok, so register to the input system */
> + rc = input_register_device(ts.dev);
> + if (rc) {
> + ret = -EIO;
> + goto fail4;
> + }
> + return 0;
> +
> +fail4:
> + disable_irq(IRQ_TC);
No need.
> + free_irq(IRQ_TC, ts.dev);
> +fail3:
> + input_free_device(ts.dev);
> +fail2:
> + s3c_adc_release(ts.adc_client);
> +fail1:
> + iounmap(base_addr);
> +fail0:
> + return ret;
> +}
> +
> +static int s3c24xx_ts_remove(struct platform_device *pdev)
__devexit.
> +{
> + disable_irq(IRQ_TC);
No need.
> + free_irq(IRQ_TC, ts.dev);
> + input_unregister_device(ts.dev);
> + input_free_device(ts.dev);
No free after unregister, input_dev is refcounted.
> + s3c_adc_release(ts.adc_client);
> + iounmap(base_addr);
> + return 0;
> +}
> +
> +#ifdef CONFIG_PM
> +static int s3c24xx_ts_suspend(struct platform_device *pdev, pm_message_t state)
> +{
> + disable_irq(IRQ_TC);
> + ts.presc = readl(base_addr + S3C2410_ADCCON);
> + ts.delay = readl(base_addr + S3C2410_ADCDLY);
> +
> + writel(TSC_SLEEP, base_addr + S3C2410_ADCTSC);
> + writel(ts.presc | S3C2410_ADCCON_STDBM, base_addr + S3C2410_ADCCON);
> + return 0;
> +}
> +
> +static int s3c24xx_ts_resume(struct platform_device *pdev)
> +{
> + /* Restore registers */
> + writel(ts.presc, base_addr + S3C2410_ADCCON);
> + writel(ts.delay, base_addr + S3C2410_ADCDLY);
> + writel(WAIT4INT(0), base_addr + S3C2410_ADCTSC);
> + enable_irq(IRQ_TC);
> + return 0;
> +}
> +
> +#else
> +#define s3c24xx_ts_suspend NULL
> +#define s3c24xx_ts_resume NULL
> +#endif
> +
> +static struct platform_driver s3c24xx_ts_driver = {
> + .driver = {
> + .name = "s3c24xx-ts",
> + .owner = THIS_MODULE,
> + },
> + .probe = s3c24xx_ts_probe,
> + .remove = s3c24xx_ts_remove,
__devexit_p().
> + .suspend = s3c24xx_ts_suspend,
This should be converted to dev_pm_ops.
> + .resume = s3c24xx_ts_resume,
> +};
> +
> +static int __init s3c24xx_ts_init(void)
> +{
> + int rc;
> +
> + rc = platform_driver_register(&s3c24xx_ts_driver);
> + return rc;
Just do "return platform_driver_register();"
> +}
> +
> +static void __exit s3c24xx_ts_exit(void)
> +{
> + platform_driver_unregister(&s3c24xx_ts_driver);
> +}
> +
> +module_init(s3c24xx_ts_init);
> +module_exit(s3c24xx_ts_exit);
> +
Thanks.
--
Dmitry
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