adc.rar_gec210

/* linux/arch/arm/mach-s5pv210/adc.c * * 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 * * Copyright (c) 2004 Arnaud Patard <arnaud.patard@rtp-net.org> * iPAQ H1940 touchscreen support * * ChangeLog * * 2004-09-05: Herbert Pötzl <herbert@13thfloor.at> * - added clock (de-)allocation code * * 2005-03-06: Arnaud Patard <arnaud.patard@rtp-net.org> * - h1940_ -> s3c24xx (this driver is now also used on the n30 * machines :P) * - Debug messages are now enabled with the config option * TOUCHSCREEN_S3C_DEBUG * - Changed the way the value are read * - Input subsystem should now work * - Use ioremap and readl/writel * * 2005-03-23: Arnaud Patard <arnaud.patard@rtp-net.org> * - Make use of some undocumented features of the touchscreen * controller * */ #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> #include <linux/delay.h> #include <linux/platform_device.h> #include <linux/miscdevice.h> #include <linux/clk.h> #include <linux/mutex.h> #include <linux/io.h> #include <linux/uaccess.h> #include <asm/irq.h> #include <mach/hardware.h> #include <linux/uaccess.h> #include <mach/regs-adc.h> #include <mach/adc.h> #include <mach/irqs.h> #define ADC_MINOR 131 #define ADC_INPUT_PIN _IOW('S', 0x0c, unsigned long) #define ADC_WITH_TOUCHSCREEN static struct clk *adc_clock; static void __iomem *base_addr; static int adc_port; struct s3c_adc_mach_info *plat_data; #ifdef ADC_WITH_TOUCHSCREEN static DEFINE_MUTEX(adc_mutex); static unsigned long data_for_ADCCON; static unsigned long data_for_ADCTSC; static void s3c_adc_save_SFR_on_ADC(void) { data_for_ADCCON = readl(base_addr + S3C_ADCCON); data_for_ADCTSC = readl(base_addr + S3C_ADCTSC); } static void s3c_adc_restore_SFR_on_ADC(void) { writel(data_for_ADCCON, base_addr + S3C_ADCCON); writel(data_for_ADCTSC, base_addr + S3C_ADCTSC); } #else static struct resource *adc_mem; #endif static int s3c_adc_open(struct inode *inode, struct file *file) { return 0; } static unsigned int s3c_adc_convert(void) { unsigned int adc_return = 0; unsigned long data0; unsigned long data1; writel((readl(base_addr + S3C_ADCCON) | S3C_ADCCON_PRSCEN) & ~S3C_ADCCON_STDBM, base_addr + S3C_ADCCON); writel((adc_port & 0xF), base_addr + S3C_ADCMUX); udelay(10); writel(readl(base_addr + S3C_ADCCON) | S3C_ADCCON_ENABLE_START, base_addr + S3C_ADCCON); do { data0 = readl(base_addr + S3C_ADCCON); } while (!(data0 & S3C_ADCCON_ECFLG)); data1 = readl(base_addr + S3C_ADCDAT0); writel((readl(base_addr + S3C_ADCCON) | S3C_ADCCON_STDBM) & ~S3C_ADCCON_PRSCEN, base_addr + S3C_ADCCON); if (plat_data->resolution == 12) adc_return = data1 & S3C_ADCDAT0_XPDATA_MASK_12BIT; else adc_return = data1 & S3C_ADCDAT0_XPDATA_MASK; return adc_return; } int s3c_adc_get_adc_data(int channel) { int adc_value = 0; int cur_adc_port = 0; #ifdef ADC_WITH_TOUCHSCREEN mutex_lock(&adc_mutex); s3c_adc_save_SFR_on_ADC(); #else mutex_lock(&adc_mutex); #endif cur_adc_port = adc_port; adc_port = channel; adc_value = s3c_adc_convert(); adc_port = cur_adc_port; #ifdef ADC_WITH_TOUCHSCREEN s3c_adc_restore_SFR_on_ADC(); mutex_unlock(&adc_mutex); #else mutex_unlock(&adc_mutex); #endif pr_debug("%s : Converted Value: %03d\n", __func__, adc_value); return adc_value; } EXPORT_SYMBOL(s3c_adc_get_adc_data); int s3c_adc_get(struct s3c_adc_request *req) { unsigned adc_channel = req->channel; int adc_value_ret = 0; adc_value_ret = s3c_adc_convert(); req->callback(adc_channel, req->param, adc_value_ret); return 0; } EXPORT_SYMBOL(s3c_adc_get); static ssize_t s3c_adc_read(struct file *file, char __user *buffer, size_t size, loff_t *pos) { int adc_value = 0; #ifdef ADC_WITH_TOUCHSCREEN mutex_lock(&adc_mutex); s3c_adc_save_SFR_on_ADC(); #endif printk(KERN_INFO "## delay: %d\n", readl(base_addr + S3C_ADCDLY)); adc_value = s3c_adc_convert(); #ifdef ADC_WITH_TOUCHSCREEN s3c_adc_restore_SFR_on_ADC(); mutex_unlock(&adc_mutex); #endif if (copy_to_user(buffer, &adc_value, sizeof(unsigned int))) return -EFAULT; return sizeof(unsigned int); } static int s3c_adc_ioctl(struct inode *inode, struct file *file, unsigned int cmd, unsigned long arg) { switch (cmd) { case ADC_INPUT_PIN: adc_port = (unsigned int) arg; if (adc_port >= 4) printk(KERN_WARNING " %d is already reserved for TouchScreen\n", adc_port); return 0; default: return -ENOIOCTLCMD; } } static const struct file_operations s3c_adc_fops = { .owner = THIS_MODULE, .read = s3c_adc_read, .open = s3c_adc_open, .ioctl = s3c_adc_ioctl, }; static struct miscdevice s3c_adc_miscdev = { .minor = ADC_MINOR, .name = "adc", .fops = &s3c_adc_fops, }; static struct s3c_adc_mach_info *s3c_adc_get_platdata(struct device *dev) { if (dev->platform_data != NULL) return (struct s3c_adc_mach_info *) dev->platform_data; else return 0; } /* * The functions for inserting/removing us as a module. */ static int __devinit s3c_adc_probe(struct platform_device *pdev) { struct resource *res; struct device *dev; int ret; int size; res = platform_get_resource(pdev, IORESOURCE_MEM, 0); dev = &pdev->dev; if (res == NULL) { dev_err(dev, "no memory resource specified\n"); return -ENOENT; } size = (res->end - res->start) + 1; #if !defined(ADC_WITH_TOUCHSCREEN) adc_mem = request_mem_region(res->start, size, pdev->name); if (adc_mem == NULL) { dev_err(dev, "failed to get memory region\n"); ret = -ENOENT; goto err_req; } #endif base_addr = ioremap(res->start, size); if (base_addr == NULL) { dev_err(dev, "fail to ioremap() region\n"); ret = -ENOENT; goto err_map; } adc_clock = clk_get(&pdev->dev, "adc"); if (IS_ERR(adc_clock)) { dev_err(dev, "failed to fine ADC clock source\n"); ret = PTR_ERR(adc_clock); goto err_clk; } clk_enable(adc_clock); /* read platform data from device struct */ plat_data = s3c_adc_get_platdata(&pdev->dev); if ((plat_data->presc & 0xff) > 0) writel(S3C_ADCCON_PRSCEN | S3C_ADCCON_PRSCVL(plat_data->presc & 0xff), base_addr + S3C_ADCCON); else writel(0, base_addr + S3C_ADCCON); /* Initialise registers */ if ((plat_data->delay & 0xffff) > 0) writel(plat_data->delay & 0xffff, base_addr + S3C_ADCDLY); if (plat_data->resolution == 12) writel(readl(base_addr + S3C_ADCCON) | S3C_ADCCON_RESSEL_12BIT, base_addr + S3C_ADCCON); writel((readl(base_addr + S3C_ADCCON) | S3C_ADCCON_STDBM) & ~S3C_ADCCON_PRSCEN, base_addr + S3C_ADCCON); ret = misc_register(&s3c_adc_miscdev); if (ret) { printk(KERN_ERR "cannot register miscdev on minor=%d (%d)\n", ADC_MINOR, ret); goto err_clk; } return 0; err_clk: clk_disable(adc_clock); clk_put(adc_clock); err_map: iounmap(base_addr); #if !defined(ADC_WITH_TOUCHSCREEN) err_req: release_resource(adc_mem); kfree(adc_mem);