diff options
Diffstat (limited to 'drivers/input/keyboard/stmp3xxx-kbd.c')
| -rw-r--r-- | drivers/input/keyboard/stmp3xxx-kbd.c | 307 |
1 files changed, 307 insertions, 0 deletions
diff --git a/drivers/input/keyboard/stmp3xxx-kbd.c b/drivers/input/keyboard/stmp3xxx-kbd.c new file mode 100644 index 000000000000..a230aa92710c --- /dev/null +++ b/drivers/input/keyboard/stmp3xxx-kbd.c @@ -0,0 +1,307 @@ +/* + * Keypad ladder driver for Freescale STMP37XX/STMP378X boards + * + * Author: dmitry pervushin <dimka@embeddedalley.com> + * + * Copyright 2008-2009 Freescale Semiconductor, Inc. All Rights Reserved. + * Copyright 2008 Embedded Alley Solutions, Inc All Rights Reserved. + */ + +/* + * The code contained herein is licensed under the GNU General Public + * License. You may obtain a copy of the GNU General Public License + * Version 2 or later at the following locations: + * + * http://www.opensource.org/licenses/gpl-license.html + * http://www.gnu.org/copyleft/gpl.html + */ +#include <linux/kernel.h> +#include <linux/module.h> +#include <linux/init.h> +#include <linux/interrupt.h> +#include <linux/input.h> +#include <linux/device.h> +#include <linux/platform_device.h> +#include <linux/pm.h> +#include <mach/regs-lradc.h> +#include <mach/lradc.h> +#include <mach/stmp3xxx.h> +#include <mach/platform.h> + +#define BUTTON_PRESS_THRESHOLD 3300 +#define LRADC_NOISE_MARGIN 100 + +/* this value represents the the lradc value at 3.3V ( 3.3V / 0.000879 V/b ) */ +#define TARGET_VDDIO_LRADC_VALUE 3754 + +struct stmpkbd_data { + struct input_dev *input; + int last_button; + int irq; + struct stmpkbd_keypair *keycodes; +}; + +static int delay1 = 500; +static int delay2 = 200; + +static int stmpkbd_open(struct input_dev *dev); +static void stmpkbd_close(struct input_dev *dev); + +static struct stmpkbd_data *stmpkbd_data_alloc(struct platform_device *pdev, + struct stmpkbd_keypair *keys) +{ + struct stmpkbd_data *d = kzalloc(sizeof(*d), GFP_KERNEL); + + if (!d) + return NULL; + + if (!keys) { + dev_err(&pdev->dev, + "No keycodes in platform_data, bailing out.\n"); + kfree(d); + return NULL; + } + d->keycodes = keys; + + d->input = input_allocate_device(); + if (!d->input) { + kfree(d); + return NULL; + } + + d->input->phys = "onboard"; + d->input->uniq = "0000'0000"; + d->input->name = pdev->name; + d->input->id.bustype = BUS_HOST; + d->input->open = stmpkbd_open; + d->input->close = stmpkbd_close; + d->input->dev.parent = &pdev->dev; + + set_bit(EV_KEY, d->input->evbit); + set_bit(EV_REL, d->input->evbit); + set_bit(EV_REP, d->input->evbit); + + + d->last_button = -1; + + while (keys->raw >= 0) { + set_bit(keys->kcode, d->input->keybit); + keys++; + } + + return d; +} + +static inline struct input_dev *GET_INPUT_DEV(struct stmpkbd_data *d) +{ + BUG_ON(!d); + return d->input; +} + +static void stmpkbd_data_free(struct stmpkbd_data *d) +{ + if (!d) + return; + if (d->input) + input_free_device(d->input); + kfree(d); +} + +static unsigned stmpkbd_decode_button(struct stmpkbd_keypair *codes, + int raw_button) + +{ + pr_debug("Decoding %d\n", raw_button); + while (codes->raw != -1) { + if ((raw_button > (codes->raw - LRADC_NOISE_MARGIN)) && + (raw_button < (codes->raw + LRADC_NOISE_MARGIN))) { + pr_debug("matches code 0x%x = %d\n", + codes->kcode, codes->kcode); + return codes->kcode; + } + codes++; + } + return (unsigned)-1; /* invalid key */ +} + + +static irqreturn_t stmpkbd_irq_handler(int irq, void *dev_id) +{ + struct platform_device *pdev = dev_id; + struct stmpkbd_data *devdata = platform_get_drvdata(pdev); + u16 raw_button, normalized_button, vddio; + unsigned btn; + + raw_button = __raw_readl(REGS_LRADC_BASE + + HW_LRADC_CHn(LRADC_CH0)) & BM_LRADC_CHn_VALUE; + vddio = hw_lradc_vddio(); + BUG_ON(vddio == 0); + + normalized_button = (raw_button * TARGET_VDDIO_LRADC_VALUE) / + vddio; + + if (normalized_button < BUTTON_PRESS_THRESHOLD && + devdata->last_button < 0) { + + btn = stmpkbd_decode_button(devdata->keycodes, + normalized_button); + + if (btn < KEY_MAX) { + devdata->last_button = btn; + input_report_key(GET_INPUT_DEV(devdata), + devdata->last_button, !0); + } else + dev_err(&pdev->dev, "Invalid button: raw = %d, " + "normalized = %d, vddio = %d\n", + raw_button, normalized_button, vddio); + } else if (devdata->last_button > 0 && + normalized_button >= BUTTON_PRESS_THRESHOLD) { + + input_report_key(GET_INPUT_DEV(devdata), + devdata->last_button, 0); + devdata->last_button = -1; + + } + + __raw_writel(BM_LRADC_CTRL1_LRADC0_IRQ, + REGS_LRADC_BASE + HW_LRADC_CTRL1_CLR); + return IRQ_HANDLED; +} + +static int stmpkbd_open(struct input_dev *dev) +{ + /* enable clock */ + return 0; +} + +static void stmpkbd_close(struct input_dev *dev) +{ + /* disable clock */ +} + +static void stmpkbd_hwinit(struct platform_device *pdev) +{ + hw_lradc_init_ladder(LRADC_CH0, LRADC_DELAY_TRIGGER_BUTTON, 200); + __raw_writel(BM_LRADC_CTRL1_LRADC0_IRQ, + REGS_LRADC_BASE + HW_LRADC_CTRL1_CLR); + __raw_writel(BM_LRADC_CTRL1_LRADC0_IRQ_EN, + REGS_LRADC_BASE + HW_LRADC_CTRL1_SET); + hw_lradc_set_delay_trigger_kick(LRADC_DELAY_TRIGGER_BUTTON, !0); +} + +static int stmpkbd_suspend(struct platform_device *pdev, pm_message_t state) +{ +#ifdef CONFIG_PM + struct input_dev *idev = platform_get_drvdata(pdev); + + hw_lradc_stop_ladder(LRADC_CH0, LRADC_DELAY_TRIGGER_BUTTON); + hw_lradc_set_delay_trigger_kick(LRADC_DELAY_TRIGGER_BUTTON, 0); + hw_lradc_unuse_channel(LRADC_CH0); + __raw_writel(BM_LRADC_CTRL1_LRADC0_IRQ_EN, + REGS_LRADC_BASE + HW_LRADC_CTRL1_CLR); + stmpkbd_close(idev); +#endif + return 0; +} + +static int stmpkbd_resume(struct platform_device *pdev) +{ +#ifdef CONFIG_PM + struct input_dev *idev = platform_get_drvdata(pdev); + + __raw_writel(BM_LRADC_CTRL1_LRADC0_IRQ_EN, + REGS_LRADC_BASE + HW_LRADC_CTRL1_SET); + stmpkbd_open(idev); + hw_lradc_use_channel(LRADC_CH0); + stmpkbd_hwinit(pdev); +#endif + return 0; +} + +static int __devinit stmpkbd_probe(struct platform_device *pdev) +{ + int err = 0; + int irq = platform_get_irq(pdev, 0); + struct stmpkbd_data *d; + + /* Create and register the input driver. */ + d = stmpkbd_data_alloc(pdev, + (struct stmpkbd_keypair *)pdev->dev.platform_data); + if (!d) { + dev_err(&pdev->dev, "Cannot allocate driver structures\n"); + err = -ENOMEM; + goto err_out; + } + + d->irq = irq; + err = request_irq(irq, stmpkbd_irq_handler, + IRQF_DISABLED, pdev->name, pdev); + if (err) { + dev_err(&pdev->dev, "Cannot request keypad IRQ\n"); + goto err_free_dev; + } + + platform_set_drvdata(pdev, d); + + /* Register the input device */ + err = input_register_device(GET_INPUT_DEV(d)); + if (err) + goto err_free_irq; + + /* these two have to be set after registering the input device */ + d->input->rep[REP_DELAY] = delay1; + d->input->rep[REP_PERIOD] = delay2; + + hw_lradc_use_channel(LRADC_CH0); + stmpkbd_hwinit(pdev); + + return 0; + +err_free_irq: + platform_set_drvdata(pdev, NULL); + free_irq(irq, pdev); +err_free_dev: + stmpkbd_data_free(d); +err_out: + return err; +} + +static int __devexit stmpkbd_remove(struct platform_device *pdev) +{ + struct stmpkbd_data *d = platform_get_drvdata(pdev); + + hw_lradc_unuse_channel(LRADC_CH0); + input_unregister_device(GET_INPUT_DEV(d)); + free_irq(d->irq, pdev); + stmpkbd_data_free(d); + + platform_set_drvdata(pdev, NULL); + + return 0; +} + +static struct platform_driver stmpkbd_driver = { + .probe = stmpkbd_probe, + .remove = __devexit_p(stmpkbd_remove), + .suspend = stmpkbd_suspend, + .resume = stmpkbd_resume, + .driver = { + .name = "stmp3xxx-keyboard", + }, +}; + +static int __init stmpkbd_init(void) +{ + return platform_driver_register(&stmpkbd_driver); +} + +static void __exit stmpkbd_exit(void) +{ + platform_driver_unregister(&stmpkbd_driver); +} + +module_init(stmpkbd_init); +module_exit(stmpkbd_exit); +MODULE_DESCRIPTION("Freescale STMP3xxxx keyboard driver"); +MODULE_AUTHOR("dmitry pervushin <dimka@embeddedalley.com>"); +MODULE_LICENSE("GPL"); |