[PATCH 2/2] Input: add wm97xx accelerated driver for AVR32 AT32AP700X microprocessors
From: Mark Brown
Date: Mon Mar 02 2009 - 08:24:26 EST
From: Hans-Christian Egtvedt <hcegtvedt@xxxxxxxxx>
This patch adds an accelerated driver for Atmel AVR32 AT32AP700X
microprocessors. It uses interrupts on the channel B in the AC97 controller.
Thus, offloading the work queue in the wm97xx-ts driver.
The driver has been tested with Atmel AVR32 AT32AP7000 and Wolfson WM9712
codec.
Signed-off-by: Hans-Christian Egtvedt <hcegtvedt@xxxxxxxxx>
Signed-off-by: Mark Brown <broonie@xxxxxxxxxxxxxxxxxxxxxxxxxxx>
---
drivers/input/touchscreen/Kconfig | 15 ++
drivers/input/touchscreen/Makefile | 1 +
drivers/input/touchscreen/at32-wm97xx.c | 410 +++++++++++++++++++++++++++++++
drivers/input/touchscreen/at32-wm97xx.h | 48 ++++
4 files changed, 474 insertions(+), 0 deletions(-)
create mode 100644 drivers/input/touchscreen/at32-wm97xx.c
create mode 100644 drivers/input/touchscreen/at32-wm97xx.h
diff --git a/drivers/input/touchscreen/Kconfig b/drivers/input/touchscreen/Kconfig
index a31d434..d63fc2f 100644
--- a/drivers/input/touchscreen/Kconfig
+++ b/drivers/input/touchscreen/Kconfig
@@ -296,6 +296,21 @@ config TOUCHSCREEN_WM9713
Say Y here to enable support for the Wolfson Microelectronics
WM9713 touchscreen controller.
+config TOUCHSCREEN_WM97XX_AT32
+ tristate "WM97xx Atmel AVR32 accelerated touch"
+ depends on TOUCHSCREEN_WM97XX && AVR32
+ help
+ Say Y here for support for streaming mode with WM97xx touchscreens on
+ Atmel AVR32 systems with an AC97 controller.
+
+ Be aware that this will use channel B in the controller for streaming
+ data, this must not conflict with other AC97 drivers.
+
+ If unsure, say N.
+
+ To compile this driver as a module, choose M here: the module will be
+ called at32-wm97xx.
+
config TOUCHSCREEN_WM97XX_MAINSTONE
tristate "WM97xx Mainstone accelerated touch"
depends on TOUCHSCREEN_WM97XX && ARCH_PXA
diff --git a/drivers/input/touchscreen/Makefile b/drivers/input/touchscreen/Makefile
index 82dd918..29a0257 100644
--- a/drivers/input/touchscreen/Makefile
+++ b/drivers/input/touchscreen/Makefile
@@ -33,5 +33,6 @@ obj-$(CONFIG_TOUCHSCREEN_DA9034) += da9034-ts.o
wm97xx-ts-$(CONFIG_TOUCHSCREEN_WM9705) += wm9705.o
wm97xx-ts-$(CONFIG_TOUCHSCREEN_WM9712) += wm9712.o
wm97xx-ts-$(CONFIG_TOUCHSCREEN_WM9713) += wm9713.o
+obj-$(CONFIG_TOUCHSCREEN_WM97XX_AT32) += at32-wm97xx.o
obj-$(CONFIG_TOUCHSCREEN_WM97XX_MAINSTONE) += mainstone-wm97xx.o
obj-$(CONFIG_TOUCHSCREEN_WM97XX_ZYLONITE) += zylonite-wm97xx.o
diff --git a/drivers/input/touchscreen/at32-wm97xx.c b/drivers/input/touchscreen/at32-wm97xx.c
new file mode 100644
index 0000000..96eeb2d
--- /dev/null
+++ b/drivers/input/touchscreen/at32-wm97xx.c
@@ -0,0 +1,410 @@
+/*
+ * Atmel AVR32 continuous touch screen driver for Wolfson WM97xx AC97 codecs.
+ *
+ * Copyright (C) 2008 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/io.h>
+#include <linux/timer.h>
+
+#include <asm/gpio.h>
+
+#include "at32-wm97xx.h"
+
+#ifdef CONFIG_CPU_AT32AP700X
+#define AT32_WM97XX_AC97C_IOMEM 0xfff02800
+#define AT32_WM97XX_AC97C_IRQ 29
+#define AT32_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");
+
+/*
+ * AT32AP700X GPIO line number.
+ *
+ * Set to GPIO number where the signal from the WM97xx device is hooked up.
+ */
+static int at32_gpio_line = AT32_WM97XX_GPIO_DEFAULT;
+module_param(at32_gpio_line, int, 0);
+MODULE_PARM_DESC(at32_gpio_line,
+ "GPIO line number on AT32AP700X connected to WM97xx");
+
+struct at32_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 at32_wm97xx_channel_b_interrupt(int irq, void *dev_id)
+{
+ struct at32_wm97xx *at32_wm97xx = dev_id;
+ struct wm97xx *wm = at32_wm97xx->wm;
+ int status = ac97c_readl(at32_wm97xx, CBSR);
+ int retval = IRQ_NONE;
+
+ if (status & AC97C_OVRUN) {
+ dev_dbg(&wm->touch_dev->dev, "AC97C overrun\n");
+ ac97c_readl(at32_wm97xx, CBRHR);
+ retval = IRQ_HANDLED;
+ } else if (status & AC97C_RXRDY) {
+ u16 data;
+ u16 value;
+ u16 source;
+ u16 pen_down;
+
+ data = ac97c_readl(at32_wm97xx, CBRHR);
+ value = data & 0x0fff;
+ source = data & WM97XX_ADCSRC_MASK;
+ pen_down = (data & WM97XX_PEN_DOWN) >> 8;
+
+ if (source == WM97XX_ADCSEL_X)
+ at32_wm97xx->x = value;
+ if (source == WM97XX_ADCSEL_Y)
+ at32_wm97xx->y = value;
+
+ if (!pressure && source == WM97XX_ADCSEL_Y) {
+ input_report_abs(wm->input_dev, ABS_X, at32_wm97xx->x);
+ input_report_abs(wm->input_dev, ABS_Y, at32_wm97xx->y);
+ input_report_abs(wm->input_dev, ABS_PRESSURE, pen_down);
+ input_sync(wm->input_dev);
+ } else if (pressure && source == WM97XX_ADCSEL_PRES) {
+ input_report_abs(wm->input_dev, ABS_X, at32_wm97xx->x);
+ input_report_abs(wm->input_dev, ABS_Y, at32_wm97xx->y);
+ input_report_abs(wm->input_dev, ABS_PRESSURE, value);
+ input_sync(wm->input_dev);
+ }
+
+ retval = IRQ_HANDLED;
+ }
+
+ return retval;
+}
+
+static void at32_wm97xx_pen_timer(unsigned long data)
+{
+ struct at32_wm97xx *at32_wm97xx = (struct at32_wm97xx *)data;
+ struct wm97xx *wm = at32_wm97xx->wm;
+ int pen_down = gpio_get_value(at32_wm97xx->gpio_pen);
+
+ if (pen_down != 0) {
+ mod_timer(&at32_wm97xx->pen_timer, jiffies
+ + msecs_to_jiffies(1));
+ } else {
+ input_report_abs(wm->input_dev, ABS_PRESSURE, 0);
+ input_sync(wm->input_dev);
+ }
+}
+
+static void at32_wm97xx_acc_pen_up(struct wm97xx *wm)
+{
+ struct at32_wm97xx *at32_wm97xx = platform_get_drvdata(wm->touch_dev);
+ int pen_down = gpio_get_value(at32_wm97xx->gpio_pen);
+
+ if (pen_down != 0) {
+ mod_timer(&at32_wm97xx->pen_timer, jiffies
+ + msecs_to_jiffies(1));
+ } else {
+ input_report_abs(wm->input_dev, ABS_PRESSURE, 0);
+ input_sync(wm->input_dev);
+ }
+}
+
+static int at32_wm97xx_acc_startup(struct wm97xx *wm)
+{
+ struct at32_wm97xx *at32_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 = at32_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(at32_wm97xx, ICA);
+ reg &= ~AC97C_CH_MASK(wm->acc_slot);
+ reg |= AC97C_CH_ASSIGN(wm->acc_slot, B);
+ ac97c_writel(at32_wm97xx, ICA, reg);
+
+ /*
+ * Enable channel and interrupt for RXRDY and OVERRUN.
+ */
+ ac97c_writel(at32_wm97xx, CBMR, AC97C_CMR_CENA
+ | AC97C_CMR_CEM_BIG
+ | AC97C_CMR_SIZE_16
+ | AC97C_OVRUN
+ | AC97C_RXRDY);
+ /* Dummy read to empty RXRHR. */
+ ac97c_readl(at32_wm97xx, CBRHR);
+ /*
+ * Enable interrupt for channel B in the AC97
+ * controller.
+ */
+ ac97c_writel(at32_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 at32_wm97xx_acc_shutdown(struct wm97xx *wm)
+{
+ if (pen_int) {
+ struct at32_wm97xx *at32_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(at32_wm97xx, ICA);
+ ica &= ~AC97C_CH_MASK(wm->acc_slot);
+ ac97c_writel(at32_wm97xx, ICA, ica);
+ ac97c_writel(at32_wm97xx, IDR, AC97C_INT_CBEVT);
+ ac97c_writel(at32_wm97xx, CBMR, 0);
+ wm->pen_irq = 0;
+ break;
+ default:
+ dev_err(&wm->touch_dev->dev, "unknown codec\n");
+ break;
+ }
+ }
+}
+
+static void at32_wm97xx_irq_enable(struct wm97xx *wm, int enable)
+{
+ /* Intentionally left empty. */
+}
+
+static struct wm97xx_mach_ops at32_mach_ops = {
+ .acc_enabled = 1,
+ .acc_pen_up = at32_wm97xx_acc_pen_up,
+ .acc_startup = at32_wm97xx_acc_startup,
+ .acc_shutdown = at32_wm97xx_acc_shutdown,
+ .irq_enable = at32_wm97xx_irq_enable,
+ .irq_gpio = WM97XX_GPIO_3,
+};
+
+static int __init at32_wm97xx_probe(struct platform_device *pdev)
+{
+ struct wm97xx *wm = platform_get_drvdata(pdev);
+ struct at32_wm97xx *at32_wm97xx;
+ int ret;
+
+ at32_wm97xx = kzalloc(sizeof(struct at32_wm97xx), GFP_KERNEL);
+ if (!at32_wm97xx) {
+ dev_dbg(&pdev->dev, "out of memory\n");
+ return -ENOMEM;
+ }
+
+ at32_wm97xx->wm = wm;
+ at32_wm97xx->regs = (void *)AT32_WM97XX_AC97C_IOMEM;
+ at32_wm97xx->ac97c_irq = AT32_WM97XX_AC97C_IRQ;
+ at32_wm97xx->gpio_pen = at32_gpio_line;
+ at32_wm97xx->gpio_irq = gpio_to_irq(at32_wm97xx->gpio_pen);
+
+ setup_timer(&at32_wm97xx->pen_timer, at32_wm97xx_pen_timer,
+ (unsigned long)at32_wm97xx);
+
+ ret = request_irq(at32_wm97xx->ac97c_irq,
+ at32_wm97xx_channel_b_interrupt,
+ IRQF_SHARED, "at32-wm97xx-ch-b", at32_wm97xx);
+ if (ret) {
+ dev_dbg(&pdev->dev, "could not request ac97c irq\n");
+ return ret;
+ }
+
+ platform_set_drvdata(pdev, at32_wm97xx);
+
+ return wm97xx_register_mach_ops(wm, &at32_mach_ops);
+}
+
+static int __exit at32_wm97xx_remove(struct platform_device *pdev)
+{
+ struct at32_wm97xx *at32_wm97xx = platform_get_drvdata(pdev);
+ struct wm97xx *wm = at32_wm97xx->wm;
+
+ ac97c_writel(at32_wm97xx, IDR, AC97C_INT_CBEVT);
+ free_irq(at32_wm97xx->ac97c_irq, at32_wm97xx);
+ wm97xx_unregister_mach_ops(wm);
+ kfree(at32_wm97xx);
+
+ platform_set_drvdata(wm->touch_dev, wm);
+
+ return 0;
+}
+
+#ifdef CONFIG_PM
+static int at32_wm97xx_suspend(struct platform_device *pdev, pm_message_t msg)
+{
+ struct at32_wm97xx *at32_wm97xx = platform_get_drvdata(pdev);
+
+ ac97c_writel(at32_wm97xx, IDR, AC97C_INT_CBEVT);
+ disable_irq(at32_wm97xx->gpio_irq);
+
+ return 0;
+}
+
+static int at32_wm97xx_resume(struct platform_device *pdev)
+{
+ struct at32_wm97xx *at32_wm97xx = platform_get_drvdata(pdev);
+ struct wm97xx *wm = at32_wm97xx->wm;
+
+ if (wm->input_dev->users) {
+ enable_irq(at32_wm97xx->gpio_irq);
+ ac97c_writel(at32_wm97xx, IER, AC97C_INT_CBEVT);
+ }
+
+ return 0;
+}
+#else
+#define at32_wm97xx_suspend NULL
+#define at32_wm97xx_resume NULL
+#endif
+
+static struct platform_driver at32_wm97xx_driver = {
+ .remove = __exit_p(at32_wm97xx_remove),
+ .driver = {
+ .name = "wm97xx-touch",
+ },
+ .suspend = at32_wm97xx_suspend,
+ .resume = at32_wm97xx_resume,
+};
+
+static int __init at32_wm97xx_init(void)
+{
+ return platform_driver_probe(&at32_wm97xx_driver, at32_wm97xx_probe);
+}
+module_init(at32_wm97xx_init);
+
+static void __exit at32_wm97xx_exit(void)
+{
+ platform_driver_unregister(&at32_wm97xx_driver);
+}
+module_exit(at32_wm97xx_exit);
+
+MODULE_AUTHOR("Hans-Christian Egtvedt <hcegtvedt@xxxxxxxxx>");
+MODULE_DESCRIPTION("wm97xx continuous touch driver for Atmel AVR32");
+MODULE_LICENSE("GPL");
diff --git a/drivers/input/touchscreen/at32-wm97xx.h b/drivers/input/touchscreen/at32-wm97xx.h
new file mode 100644
index 0000000..7d754d8
--- /dev/null
+++ b/drivers/input/touchscreen/at32-wm97xx.h
@@ -0,0 +1,48 @@
+/*
+ * Atmel AVR32 continuous touch screen driver for Wolfson WM97xx AC97 codecs.
+ *
+ * Copyright (C) 2008 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.
+ */
+
+#ifndef _AT32_WM97XX_H
+#define _AT32_WM97XX_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)
+
+#endif /* _AT32_WM97XX_H */
--
1.6.1.3
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