/* * 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> #include <linux/slab.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_ADCSEL_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: 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); kfree(atmel_wm97xx); return 0; } #ifdef CONFIG_PM_SLEEP static int atmel_wm97xx_suspend(struct device *dev) { struct platform_device *pdev = to_platform_device(dev); 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 device *dev) { struct platform_device *pdev = to_platform_device(dev); 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; } #endif static SIMPLE_DEV_PM_OPS(atmel_wm97xx_pm_ops, atmel_wm97xx_suspend, atmel_wm97xx_resume); static struct platform_driver atmel_wm97xx_driver = { .remove = __exit_p(atmel_wm97xx_remove), .driver = { .name = "wm97xx-touch", .pm = &atmel_wm97xx_pm_ops, }, }; module_platform_driver_probe(atmel_wm97xx_driver, atmel_wm97xx_probe); MODULE_AUTHOR("Hans-Christian Egtvedt <egtvedt@samfundet.no>"); MODULE_DESCRIPTION("wm97xx continuous touch driver for Atmel AT91 and AVR32"); MODULE_LICENSE("GPL");