diff options
Diffstat (limited to 'drivers/input/touchscreen/mainstone-wm97xx.c')
| -rw-r--r-- | drivers/input/touchscreen/mainstone-wm97xx.c | 302 |
1 files changed, 302 insertions, 0 deletions
diff --git a/drivers/input/touchscreen/mainstone-wm97xx.c b/drivers/input/touchscreen/mainstone-wm97xx.c new file mode 100644 index 000000000000..a79f029b91c0 --- /dev/null +++ b/drivers/input/touchscreen/mainstone-wm97xx.c @@ -0,0 +1,302 @@ +/* + * mainstone-wm97xx.c -- Mainstone Continuous Touch screen driver for + * Wolfson WM97xx AC97 Codecs. + * + * Copyright 2004, 2007 Wolfson Microelectronics PLC. + * Author: Liam Girdwood + * liam.girdwood@wolfsonmicro.com or linux@wolfsonmicro.com + * Parts Copyright : Ian Molton <spyro@f2s.com> + * Andrew Zabolotny <zap@homelink.ru> + * + * 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. + * + * Notes: + * This is a wm97xx extended touch driver to capture touch + * data in a continuous manner on the Intel XScale archictecture + * + * Features: + * - codecs supported:- WM9705, WM9712, WM9713 + * - processors supported:- Intel XScale PXA25x, PXA26x, PXA27x + * + */ + +#include <linux/module.h> +#include <linux/moduleparam.h> +#include <linux/version.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/io.h> +#include <asm/arch/pxa-regs.h> + +#define VERSION "0.13" + +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; +static u16 last, tries; + +/* + * Pen sampling frequency (Hz) in continuous mode. + */ +static int cont_rate = 200; +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; +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"); + + +/* flush AC97 slot 5 FIFO on pxa machines */ +#ifdef CONFIG_PXA27x +static void wm97xx_acc_pen_up(struct wm97xx *wm) +{ + schedule_timeout_uninterruptible(1); + + while (MISR & (1 << 2)) + MODR; +} +#else +static void wm97xx_acc_pen_up(struct wm97xx *wm) +{ + int count = 16; + schedule_timeout_uninterruptible(1); + + while (count < 16) { + MODR; + count--; + } +} +#endif + +static int wm97xx_acc_pen_down(struct wm97xx *wm) +{ + u16 x, y, p = 0x100 | WM97XX_ADCSEL_PRES; + int reads = 0; + + /* When the AC97 queue has been drained we need to allow time + * to buffer up samples otherwise we end up spinning polling + * for samples. The controller can't have a suitably low + * threashold set to use the notifications it gives. + */ + schedule_timeout_uninterruptible(1); + + if (tries > 5) { + tries = 0; + return RC_PENUP; + } + + x = MODR; + if (x == last) { + tries++; + return RC_AGAIN; + } + last = x; + do { + if (reads) + x = MODR; + y = MODR; + if (pressure) + p = MODR; + + /* are samples valid */ + if ((x & WM97XX_ADCSRC_MASK) != WM97XX_ADCSEL_X || + (y & WM97XX_ADCSRC_MASK) != WM97XX_ADCSEL_Y || + (p & WM97XX_ADCSRC_MASK) != WM97XX_ADCSEL_PRES) + goto up; + + /* coordinate is good */ + tries = 0; + input_report_abs(wm->input_dev, ABS_X, x & 0xfff); + input_report_abs(wm->input_dev, ABS_Y, y & 0xfff); + input_report_abs(wm->input_dev, ABS_PRESSURE, p & 0xfff); + input_sync(wm->input_dev); + reads++; + } while (reads < cinfo[sp_idx].reads); +up: + return RC_PENDOWN | RC_AGAIN; +} + +static int wm97xx_acc_startup(struct wm97xx *wm) +{ + int idx = 0; + + /* check we have a codec */ + if (wm->ac97 == NULL) + return -ENODEV; + + /* Go you big red fire engine */ + 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->dev, + "mainstone accelerated touchscreen driver, %d samples/sec\n", + cinfo[sp_idx].speed); + + /* codec specific irq config */ + if (pen_int) { + switch (wm->id) { + case WM9705_ID2: + wm->pen_irq = IRQ_GPIO(4); + set_irq_type(IRQ_GPIO(4), IRQT_BOTHEDGE); + break; + case WM9712_ID2: + case WM9713_ID2: + /* enable pen down interrupt */ + /* use PEN_DOWN GPIO 13 to assert IRQ on GPIO line 2 */ + wm->pen_irq = MAINSTONE_AC97_IRQ; + 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_2, WM97XX_GPIO_OUT, + WM97XX_GPIO_POL_HIGH, + WM97XX_GPIO_NOTSTICKY, + WM97XX_GPIO_NOWAKE); + break; + default: + dev_err(wm->dev, + "pen down irq not supported on this device\n"); + pen_int = 0; + break; + } + } + + return 0; +} + +static void wm97xx_acc_shutdown(struct wm97xx *wm) +{ + /* codec specific deconfig */ + if (pen_int) { + switch (wm->id & 0xffff) { + case WM9705_ID2: + wm->pen_irq = 0; + break; + case WM9712_ID2: + case WM9713_ID2: + /* disable interrupt */ + wm->pen_irq = 0; + break; + } + } +} + +static void wm97xx_irq_enable(struct wm97xx *wm, int enable) +{ + if (enable) + enable_irq(wm->pen_irq); + else + disable_irq(wm->pen_irq); +} + +static struct wm97xx_mach_ops mainstone_mach_ops = { + .acc_enabled = 1, + .acc_pen_up = wm97xx_acc_pen_up, + .acc_pen_down = wm97xx_acc_pen_down, + .acc_startup = wm97xx_acc_startup, + .acc_shutdown = wm97xx_acc_shutdown, + .irq_enable = wm97xx_irq_enable, + .irq_gpio = WM97XX_GPIO_2, +}; + +static int mainstone_wm97xx_probe(struct platform_device *pdev) +{ + struct wm97xx *wm = platform_get_drvdata(pdev); + + return wm97xx_register_mach_ops(wm, &mainstone_mach_ops); +} + +static int mainstone_wm97xx_remove(struct platform_device *pdev) +{ + struct wm97xx *wm = platform_get_drvdata(pdev); + + wm97xx_unregister_mach_ops(wm); + return 0; +} + +static struct platform_driver mainstone_wm97xx_driver = { + .probe = mainstone_wm97xx_probe, + .remove = mainstone_wm97xx_remove, + .driver = { + .name = "wm97xx-touch", + }, +}; + +static int __init mainstone_wm97xx_init(void) +{ + return platform_driver_register(&mainstone_wm97xx_driver); +} + +static void __exit mainstone_wm97xx_exit(void) +{ + platform_driver_unregister(&mainstone_wm97xx_driver); +} + +module_init(mainstone_wm97xx_init); +module_exit(mainstone_wm97xx_exit); + +/* Module information */ +MODULE_AUTHOR("Liam Girdwood <liam.girdwood@wolfsonmicro.com>"); +MODULE_DESCRIPTION("wm97xx continuous touch driver for mainstone"); +MODULE_LICENSE("GPL"); |