| /* |
| * Atmel AT91 and AVR32 continuous touch screen driver for Wolfson WM97xx AC97 |
| * codecs. |
| * |
| * Copyright (C) 2008 - 2009 Atmel Corporation |
| * |
| * 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/module.h> |
| #include <linux/moduleparam.h> |
| #include <linux/kernel.h> |
| #include <linux/init.h> |
| #include <linux/delay.h> |
| #include <linux/irq.h> |
| #include <linux/interrupt.h> |
| #include <linux/wm97xx.h> |
| #include <linux/timer.h> |
| #include <linux/gpio.h> |
| #include <linux/io.h> |
| |
| #define AC97C_ICA 0x10 |
| #define AC97C_CBRHR 0x30 |
| #define AC97C_CBSR 0x38 |
| #define AC97C_CBMR 0x3c |
| #define AC97C_IER 0x54 |
| #define AC97C_IDR 0x58 |
| |
| #define AC97C_RXRDY (1 << 4) |
| #define AC97C_OVRUN (1 << 5) |
| |
| #define AC97C_CMR_SIZE_20 (0 << 16) |
| #define AC97C_CMR_SIZE_18 (1 << 16) |
| #define AC97C_CMR_SIZE_16 (2 << 16) |
| #define AC97C_CMR_SIZE_10 (3 << 16) |
| #define AC97C_CMR_CEM_LITTLE (1 << 18) |
| #define AC97C_CMR_CEM_BIG (0 << 18) |
| #define AC97C_CMR_CENA (1 << 21) |
| |
| #define AC97C_INT_CBEVT (1 << 4) |
| |
| #define AC97C_SR_CAEVT (1 << 3) |
| |
| #define AC97C_CH_MASK(slot) \ |
| (0x7 << (3 * (slot - 3))) |
| #define AC97C_CH_ASSIGN(slot, channel) \ |
| (AC97C_CHANNEL_##channel << (3 * (slot - 3))) |
| #define AC97C_CHANNEL_NONE 0x0 |
| #define AC97C_CHANNEL_B 0x2 |
| |
| #define ac97c_writel(chip, reg, val) \ |
| __raw_writel((val), (chip)->regs + AC97C_##reg) |
| #define ac97c_readl(chip, reg) \ |
| __raw_readl((chip)->regs + AC97C_##reg) |
| |
| #ifdef CONFIG_CPU_AT32AP700X |
| #define ATMEL_WM97XX_AC97C_IOMEM (0xfff02800) |
| #define ATMEL_WM97XX_AC97C_IRQ (29) |
| #define ATMEL_WM97XX_GPIO_DEFAULT (32+16) /* Pin 16 on port B. */ |
| #else |
| #error Unknown CPU, this driver only supports AT32AP700X CPUs. |
| #endif |
| |
| struct continuous { |
| u16 id; /* codec id */ |
| u8 code; /* continuous code */ |
| u8 reads; /* number of coord reads per read cycle */ |
| u32 speed; /* number of coords per second */ |
| }; |
| |
| #define WM_READS(sp) ((sp / HZ) + 1) |
| |
| static const struct continuous cinfo[] = { |
| {WM9705_ID2, 0, WM_READS(94), 94}, |
| {WM9705_ID2, 1, WM_READS(188), 188}, |
| {WM9705_ID2, 2, WM_READS(375), 375}, |
| {WM9705_ID2, 3, WM_READS(750), 750}, |
| {WM9712_ID2, 0, WM_READS(94), 94}, |
| {WM9712_ID2, 1, WM_READS(188), 188}, |
| {WM9712_ID2, 2, WM_READS(375), 375}, |
| {WM9712_ID2, 3, WM_READS(750), 750}, |
| {WM9713_ID2, 0, WM_READS(94), 94}, |
| {WM9713_ID2, 1, WM_READS(120), 120}, |
| {WM9713_ID2, 2, WM_READS(154), 154}, |
| {WM9713_ID2, 3, WM_READS(188), 188}, |
| }; |
| |
| /* Continuous speed index. */ |
| static int sp_idx; |
| |
| /* |
| * Pen sampling frequency (Hz) in continuous mode. |
| */ |
| static int cont_rate = 188; |
| module_param(cont_rate, int, 0); |
| MODULE_PARM_DESC(cont_rate, "Sampling rate in continuous mode (Hz)"); |
| |
| /* |
| * Pen down detection. |
| * |
| * This driver can either poll or use an interrupt to indicate a pen down |
| * event. If the irq request fails then it will fall back to polling mode. |
| */ |
| static int pen_int = 1; |
| module_param(pen_int, int, 0); |
| MODULE_PARM_DESC(pen_int, "Pen down detection (1 = interrupt, 0 = polling)"); |
| |
| /* |
| * Pressure readback. |
| * |
| * Set to 1 to read back pen down pressure. |
| */ |
| static int pressure; |
| module_param(pressure, int, 0); |
| MODULE_PARM_DESC(pressure, "Pressure readback (1 = pressure, 0 = no pressure)"); |
| |
| /* |
| * AC97 touch data slot. |
| * |
| * Touch screen readback data ac97 slot. |
| */ |
| static int ac97_touch_slot = 5; |
| module_param(ac97_touch_slot, int, 0); |
| MODULE_PARM_DESC(ac97_touch_slot, "Touch screen data slot AC97 number"); |
| |
| /* |
| * GPIO line number. |
| * |
| * Set to GPIO number where the signal from the WM97xx device is hooked up. |
| */ |
| static int atmel_gpio_line = ATMEL_WM97XX_GPIO_DEFAULT; |
| module_param(atmel_gpio_line, int, 0); |
| MODULE_PARM_DESC(atmel_gpio_line, "GPIO line number connected to WM97xx"); |
| |
| struct atmel_wm97xx { |
| struct wm97xx *wm; |
| struct timer_list pen_timer; |
| void __iomem *regs; |
| unsigned long ac97c_irq; |
| unsigned long gpio_pen; |
| unsigned long gpio_irq; |
| unsigned short x; |
| unsigned short y; |
| }; |
| |
| static irqreturn_t atmel_wm97xx_channel_b_interrupt(int irq, void *dev_id) |
| { |
| struct atmel_wm97xx *atmel_wm97xx = dev_id; |
| struct wm97xx *wm = atmel_wm97xx->wm; |
| int status = ac97c_readl(atmel_wm97xx, CBSR); |
| irqreturn_t retval = IRQ_NONE; |
| |
| if (status & AC97C_OVRUN) { |
| dev_dbg(&wm->touch_dev->dev, "AC97C overrun\n"); |
| ac97c_readl(atmel_wm97xx, CBRHR); |
| retval = IRQ_HANDLED; |
| } else if (status & AC97C_RXRDY) { |
| u16 data; |
| u16 value; |
| u16 source; |
| u16 pen_down; |
| |
| data = ac97c_readl(atmel_wm97xx, CBRHR); |
| value = data & 0x0fff; |
| source = data & WM97XX_ADCSRC_MASK; |
| pen_down = (data & WM97XX_PEN_DOWN) >> 8; |
| |
| if (source == WM97XX_ADCSEL_X) |
| atmel_wm97xx->x = value; |
| if (source == WM97XX_ADCSEL_Y) |
| atmel_wm97xx->y = value; |
| |
| if (!pressure && source == WM97XX_ADCSEL_Y) { |
| input_report_abs(wm->input_dev, ABS_X, atmel_wm97xx->x); |
| input_report_abs(wm->input_dev, ABS_Y, atmel_wm97xx->y); |
| input_report_key(wm->input_dev, BTN_TOUCH, pen_down); |
| input_sync(wm->input_dev); |
| } else if (pressure && source == WM97XX_ADCSEL_PRES) { |
| input_report_abs(wm->input_dev, ABS_X, atmel_wm97xx->x); |
| input_report_abs(wm->input_dev, ABS_Y, atmel_wm97xx->y); |
| input_report_abs(wm->input_dev, ABS_PRESSURE, value); |
| input_report_key(wm->input_dev, BTN_TOUCH, value); |
| input_sync(wm->input_dev); |
| } |
| |
| retval = IRQ_HANDLED; |
| } |
| |
| return retval; |
| } |
| |
| static void atmel_wm97xx_acc_pen_up(struct wm97xx *wm) |
| { |
| struct atmel_wm97xx *atmel_wm97xx = platform_get_drvdata(wm->touch_dev); |
| struct input_dev *input_dev = wm->input_dev; |
| int pen_down = gpio_get_value(atmel_wm97xx->gpio_pen); |
| |
| if (pen_down != 0) { |
| mod_timer(&atmel_wm97xx->pen_timer, |
| jiffies + msecs_to_jiffies(1)); |
| } else { |
| if (pressure) |
| input_report_abs(input_dev, ABS_PRESSURE, 0); |
| input_report_key(input_dev, BTN_TOUCH, 0); |
| input_sync(input_dev); |
| } |
| } |
| |
| static void atmel_wm97xx_pen_timer(unsigned long data) |
| { |
| atmel_wm97xx_acc_pen_up((struct wm97xx *)data); |
| } |
| |
| static int atmel_wm97xx_acc_startup(struct wm97xx *wm) |
| { |
| struct atmel_wm97xx *atmel_wm97xx = platform_get_drvdata(wm->touch_dev); |
| int idx = 0; |
| |
| if (wm->ac97 == NULL) |
| return -ENODEV; |
| |
| for (idx = 0; idx < ARRAY_SIZE(cinfo); idx++) { |
| if (wm->id != cinfo[idx].id) |
| continue; |
| |
| sp_idx = idx; |
| |
| if (cont_rate <= cinfo[idx].speed) |
| break; |
| } |
| |
| wm->acc_rate = cinfo[sp_idx].code; |
| wm->acc_slot = ac97_touch_slot; |
| dev_info(&wm->touch_dev->dev, "atmel accelerated touchscreen driver, " |
| "%d samples/sec\n", cinfo[sp_idx].speed); |
| |
| if (pen_int) { |
| unsigned long reg; |
| |
| wm->pen_irq = atmel_wm97xx->gpio_irq; |
| |
| switch (wm->id) { |
| case WM9712_ID2: /* Fall through. */ |
| case WM9713_ID2: |
| /* |
| * Use GPIO 13 (PEN_DOWN) to assert GPIO line 3 |
| * (PENDOWN). |
| */ |
| wm97xx_config_gpio(wm, WM97XX_GPIO_13, WM97XX_GPIO_IN, |
| WM97XX_GPIO_POL_HIGH, |
| WM97XX_GPIO_STICKY, |
| WM97XX_GPIO_WAKE); |
| wm97xx_config_gpio(wm, WM97XX_GPIO_3, WM97XX_GPIO_OUT, |
| WM97XX_GPIO_POL_HIGH, |
| WM97XX_GPIO_NOTSTICKY, |
| WM97XX_GPIO_NOWAKE); |
| case WM9705_ID2: /* Fall through. */ |
| /* |
| * Enable touch data slot in AC97 controller channel B. |
| */ |
| reg = ac97c_readl(atmel_wm97xx, ICA); |
| reg &= ~AC97C_CH_MASK(wm->acc_slot); |
| reg |= AC97C_CH_ASSIGN(wm->acc_slot, B); |
| ac97c_writel(atmel_wm97xx, ICA, reg); |
| |
| /* |
| * Enable channel and interrupt for RXRDY and OVERRUN. |
| */ |
| ac97c_writel(atmel_wm97xx, CBMR, AC97C_CMR_CENA |
| | AC97C_CMR_CEM_BIG |
| | AC97C_CMR_SIZE_16 |
| | AC97C_OVRUN |
| | AC97C_RXRDY); |
| /* Dummy read to empty RXRHR. */ |
| ac97c_readl(atmel_wm97xx, CBRHR); |
| /* |
| * Enable interrupt for channel B in the AC97 |
| * controller. |
| */ |
| ac97c_writel(atmel_wm97xx, IER, AC97C_INT_CBEVT); |
| break; |
| default: |
| dev_err(&wm->touch_dev->dev, "pen down irq not " |
| "supported on this device\n"); |
| pen_int = 0; |
| break; |
| } |
| } |
| |
| return 0; |
| } |
| |
| static void atmel_wm97xx_acc_shutdown(struct wm97xx *wm) |
| { |
| if (pen_int) { |
| struct atmel_wm97xx *atmel_wm97xx = |
| platform_get_drvdata(wm->touch_dev); |
| unsigned long ica; |
| |
| switch (wm->id & 0xffff) { |
| case WM9705_ID2: /* Fall through. */ |
| case WM9712_ID2: /* Fall through. */ |
| case WM9713_ID2: |
| /* Disable slot and turn off channel B interrupts. */ |
| ica = ac97c_readl(atmel_wm97xx, ICA); |
| ica &= ~AC97C_CH_MASK(wm->acc_slot); |
| ac97c_writel(atmel_wm97xx, ICA, ica); |
| ac97c_writel(atmel_wm97xx, IDR, AC97C_INT_CBEVT); |
| ac97c_writel(atmel_wm97xx, CBMR, 0); |
| wm->pen_irq = 0; |
| break; |
| default: |
| dev_err(&wm->touch_dev->dev, "unknown codec\n"); |
| break; |
| } |
| } |
| } |
| |
| static void atmel_wm97xx_irq_enable(struct wm97xx *wm, int enable) |
| { |
| /* Intentionally left empty. */ |
| } |
| |
| static struct wm97xx_mach_ops atmel_mach_ops = { |
| .acc_enabled = 1, |
| .acc_pen_up = atmel_wm97xx_acc_pen_up, |
| .acc_startup = atmel_wm97xx_acc_startup, |
| .acc_shutdown = atmel_wm97xx_acc_shutdown, |
| .irq_enable = atmel_wm97xx_irq_enable, |
| .irq_gpio = WM97XX_GPIO_3, |
| }; |
| |
| static int __init atmel_wm97xx_probe(struct platform_device *pdev) |
| { |
| struct wm97xx *wm = platform_get_drvdata(pdev); |
| struct atmel_wm97xx *atmel_wm97xx; |
| int ret; |
| |
| atmel_wm97xx = kzalloc(sizeof(struct atmel_wm97xx), GFP_KERNEL); |
| if (!atmel_wm97xx) { |
| dev_dbg(&pdev->dev, "out of memory\n"); |
| return -ENOMEM; |
| } |
| |
| atmel_wm97xx->wm = wm; |
| atmel_wm97xx->regs = (void *)ATMEL_WM97XX_AC97C_IOMEM; |
| atmel_wm97xx->ac97c_irq = ATMEL_WM97XX_AC97C_IRQ; |
| atmel_wm97xx->gpio_pen = atmel_gpio_line; |
| atmel_wm97xx->gpio_irq = gpio_to_irq(atmel_wm97xx->gpio_pen); |
| |
| setup_timer(&atmel_wm97xx->pen_timer, atmel_wm97xx_pen_timer, |
| (unsigned long)wm); |
| |
| ret = request_irq(atmel_wm97xx->ac97c_irq, |
| atmel_wm97xx_channel_b_interrupt, |
| IRQF_SHARED, "atmel-wm97xx-ch-b", atmel_wm97xx); |
| if (ret) { |
| dev_dbg(&pdev->dev, "could not request ac97c irq\n"); |
| goto err; |
| } |
| |
| platform_set_drvdata(pdev, atmel_wm97xx); |
| |
| ret = wm97xx_register_mach_ops(wm, &atmel_mach_ops); |
| if (ret) |
| goto err_irq; |
| |
| return ret; |
| |
| err_irq: |
| free_irq(atmel_wm97xx->ac97c_irq, atmel_wm97xx); |
| err: |
| platform_set_drvdata(pdev, NULL); |
| kfree(atmel_wm97xx); |
| return ret; |
| } |
| |
| static int __exit atmel_wm97xx_remove(struct platform_device *pdev) |
| { |
| struct atmel_wm97xx *atmel_wm97xx = platform_get_drvdata(pdev); |
| struct wm97xx *wm = atmel_wm97xx->wm; |
| |
| ac97c_writel(atmel_wm97xx, IDR, AC97C_INT_CBEVT); |
| free_irq(atmel_wm97xx->ac97c_irq, atmel_wm97xx); |
| del_timer_sync(&atmel_wm97xx->pen_timer); |
| wm97xx_unregister_mach_ops(wm); |
| platform_set_drvdata(pdev, NULL); |
| kfree(atmel_wm97xx); |
| |
| return 0; |
| } |
| |
| #ifdef CONFIG_PM |
| static int atmel_wm97xx_suspend(struct platform_device *pdev, pm_message_t msg) |
| { |
| struct atmel_wm97xx *atmel_wm97xx = platform_get_drvdata(pdev); |
| |
| ac97c_writel(atmel_wm97xx, IDR, AC97C_INT_CBEVT); |
| disable_irq(atmel_wm97xx->gpio_irq); |
| del_timer_sync(&atmel_wm97xx->pen_timer); |
| |
| return 0; |
| } |
| |
| static int atmel_wm97xx_resume(struct platform_device *pdev) |
| { |
| struct atmel_wm97xx *atmel_wm97xx = platform_get_drvdata(pdev); |
| struct wm97xx *wm = atmel_wm97xx->wm; |
| |
| if (wm->input_dev->users) { |
| enable_irq(atmel_wm97xx->gpio_irq); |
| ac97c_writel(atmel_wm97xx, IER, AC97C_INT_CBEVT); |
| } |
| |
| return 0; |
| } |
| #else |
| #define atmel_wm97xx_suspend NULL |
| #define atmel_wm97xx_resume NULL |
| #endif |
| |
| static struct platform_driver atmel_wm97xx_driver = { |
| .remove = __exit_p(atmel_wm97xx_remove), |
| .driver = { |
| .name = "wm97xx-touch", |
| }, |
| .suspend = atmel_wm97xx_suspend, |
| .resume = atmel_wm97xx_resume, |
| }; |
| |
| static int __init atmel_wm97xx_init(void) |
| { |
| return platform_driver_probe(&atmel_wm97xx_driver, atmel_wm97xx_probe); |
| } |
| module_init(atmel_wm97xx_init); |
| |
| static void __exit atmel_wm97xx_exit(void) |
| { |
| platform_driver_unregister(&atmel_wm97xx_driver); |
| } |
| module_exit(atmel_wm97xx_exit); |
| |
| MODULE_AUTHOR("Hans-Christian Egtvedt <hans-christian.egtvedt@atmel.com>"); |
| MODULE_DESCRIPTION("wm97xx continuous touch driver for Atmel AT91 and AVR32"); |
| MODULE_LICENSE("GPL"); |