diff options
Diffstat (limited to 'drivers/input/touchscreen/atmel-wm97xx.c')
| -rw-r--r-- | drivers/input/touchscreen/atmel-wm97xx.c | 446 |
1 files changed, 446 insertions, 0 deletions
diff --git a/drivers/input/touchscreen/atmel-wm97xx.c b/drivers/input/touchscreen/atmel-wm97xx.c new file mode 100644 index 0000000..35377f5 --- /dev/null +++ b/drivers/input/touchscreen/atmel-wm97xx.c @@ -0,0 +1,446 @@ +/* + * 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 Unkown 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"); |