diff options
Diffstat (limited to 'drivers/input/keyboard/davinci_keyscan.c')
-rw-r--r-- | drivers/input/keyboard/davinci_keyscan.c | 315 |
1 files changed, 315 insertions, 0 deletions
diff --git a/drivers/input/keyboard/davinci_keyscan.c b/drivers/input/keyboard/davinci_keyscan.c new file mode 100644 index 000000000..f489cd585 --- /dev/null +++ b/drivers/input/keyboard/davinci_keyscan.c @@ -0,0 +1,315 @@ +// SPDX-License-Identifier: GPL-2.0-or-later +/* + * DaVinci Key Scan Driver for TI platforms + * + * Copyright (C) 2009 Texas Instruments, Inc + * + * Author: Miguel Aguilar <miguel.aguilar@ridgerun.com> + * + * Initial Code: Sandeep Paulraj <s-paulraj@ti.com> + */ +#include <linux/module.h> +#include <linux/init.h> +#include <linux/interrupt.h> +#include <linux/types.h> +#include <linux/input.h> +#include <linux/kernel.h> +#include <linux/delay.h> +#include <linux/platform_device.h> +#include <linux/errno.h> +#include <linux/slab.h> + +#include <linux/platform_data/keyscan-davinci.h> + +/* Key scan registers */ +#define DAVINCI_KEYSCAN_KEYCTRL 0x0000 +#define DAVINCI_KEYSCAN_INTENA 0x0004 +#define DAVINCI_KEYSCAN_INTFLAG 0x0008 +#define DAVINCI_KEYSCAN_INTCLR 0x000c +#define DAVINCI_KEYSCAN_STRBWIDTH 0x0010 +#define DAVINCI_KEYSCAN_INTERVAL 0x0014 +#define DAVINCI_KEYSCAN_CONTTIME 0x0018 +#define DAVINCI_KEYSCAN_CURRENTST 0x001c +#define DAVINCI_KEYSCAN_PREVSTATE 0x0020 +#define DAVINCI_KEYSCAN_EMUCTRL 0x0024 +#define DAVINCI_KEYSCAN_IODFTCTRL 0x002c + +/* Key Control Register (KEYCTRL) */ +#define DAVINCI_KEYSCAN_KEYEN 0x00000001 +#define DAVINCI_KEYSCAN_PREVMODE 0x00000002 +#define DAVINCI_KEYSCAN_CHATOFF 0x00000004 +#define DAVINCI_KEYSCAN_AUTODET 0x00000008 +#define DAVINCI_KEYSCAN_SCANMODE 0x00000010 +#define DAVINCI_KEYSCAN_OUTTYPE 0x00000020 + +/* Masks for the interrupts */ +#define DAVINCI_KEYSCAN_INT_CONT 0x00000008 +#define DAVINCI_KEYSCAN_INT_OFF 0x00000004 +#define DAVINCI_KEYSCAN_INT_ON 0x00000002 +#define DAVINCI_KEYSCAN_INT_CHANGE 0x00000001 +#define DAVINCI_KEYSCAN_INT_ALL 0x0000000f + +struct davinci_ks { + struct input_dev *input; + struct davinci_ks_platform_data *pdata; + int irq; + void __iomem *base; + resource_size_t pbase; + size_t base_size; + unsigned short keymap[]; +}; + +/* Initializing the kp Module */ +static int __init davinci_ks_initialize(struct davinci_ks *davinci_ks) +{ + struct device *dev = &davinci_ks->input->dev; + struct davinci_ks_platform_data *pdata = davinci_ks->pdata; + u32 matrix_ctrl; + + /* Enable all interrupts */ + __raw_writel(DAVINCI_KEYSCAN_INT_ALL, + davinci_ks->base + DAVINCI_KEYSCAN_INTENA); + + /* Clear interrupts if any */ + __raw_writel(DAVINCI_KEYSCAN_INT_ALL, + davinci_ks->base + DAVINCI_KEYSCAN_INTCLR); + + /* Setup the scan period = strobe + interval */ + __raw_writel(pdata->strobe, + davinci_ks->base + DAVINCI_KEYSCAN_STRBWIDTH); + __raw_writel(pdata->interval, + davinci_ks->base + DAVINCI_KEYSCAN_INTERVAL); + __raw_writel(0x01, + davinci_ks->base + DAVINCI_KEYSCAN_CONTTIME); + + /* Define matrix type */ + switch (pdata->matrix_type) { + case DAVINCI_KEYSCAN_MATRIX_4X4: + matrix_ctrl = 0; + break; + case DAVINCI_KEYSCAN_MATRIX_5X3: + matrix_ctrl = (1 << 6); + break; + default: + dev_err(dev->parent, "wrong matrix type\n"); + return -EINVAL; + } + + /* Enable key scan module and set matrix type */ + __raw_writel(DAVINCI_KEYSCAN_AUTODET | DAVINCI_KEYSCAN_KEYEN | + matrix_ctrl, davinci_ks->base + DAVINCI_KEYSCAN_KEYCTRL); + + return 0; +} + +static irqreturn_t davinci_ks_interrupt(int irq, void *dev_id) +{ + struct davinci_ks *davinci_ks = dev_id; + struct device *dev = &davinci_ks->input->dev; + unsigned short *keymap = davinci_ks->keymap; + int keymapsize = davinci_ks->pdata->keymapsize; + u32 prev_status, new_status, changed; + bool release; + int keycode = KEY_UNKNOWN; + int i; + + /* Disable interrupt */ + __raw_writel(0x0, davinci_ks->base + DAVINCI_KEYSCAN_INTENA); + + /* Reading previous and new status of the key scan */ + prev_status = __raw_readl(davinci_ks->base + DAVINCI_KEYSCAN_PREVSTATE); + new_status = __raw_readl(davinci_ks->base + DAVINCI_KEYSCAN_CURRENTST); + + changed = prev_status ^ new_status; + + if (changed) { + /* + * It goes through all bits in 'changed' to ensure + * that no key changes are being missed + */ + for (i = 0 ; i < keymapsize; i++) { + if ((changed>>i) & 0x1) { + keycode = keymap[i]; + release = (new_status >> i) & 0x1; + dev_dbg(dev->parent, "key %d %s\n", keycode, + release ? "released" : "pressed"); + input_report_key(davinci_ks->input, keycode, + !release); + input_sync(davinci_ks->input); + } + } + /* Clearing interrupt */ + __raw_writel(DAVINCI_KEYSCAN_INT_ALL, + davinci_ks->base + DAVINCI_KEYSCAN_INTCLR); + } + + /* Enable interrupts */ + __raw_writel(0x1, davinci_ks->base + DAVINCI_KEYSCAN_INTENA); + + return IRQ_HANDLED; +} + +static int __init davinci_ks_probe(struct platform_device *pdev) +{ + struct davinci_ks *davinci_ks; + struct input_dev *key_dev; + struct resource *res, *mem; + struct device *dev = &pdev->dev; + struct davinci_ks_platform_data *pdata = dev_get_platdata(dev); + int error, i; + + if (pdata->device_enable) { + error = pdata->device_enable(dev); + if (error < 0) { + dev_dbg(dev, "device enable function failed\n"); + return error; + } + } + + if (!pdata->keymap) { + dev_dbg(dev, "no keymap from pdata\n"); + return -EINVAL; + } + + davinci_ks = kzalloc(sizeof(struct davinci_ks) + + sizeof(unsigned short) * pdata->keymapsize, GFP_KERNEL); + if (!davinci_ks) { + dev_dbg(dev, "could not allocate memory for private data\n"); + return -ENOMEM; + } + + memcpy(davinci_ks->keymap, pdata->keymap, + sizeof(unsigned short) * pdata->keymapsize); + + key_dev = input_allocate_device(); + if (!key_dev) { + dev_dbg(dev, "could not allocate input device\n"); + error = -ENOMEM; + goto fail1; + } + + davinci_ks->input = key_dev; + + davinci_ks->irq = platform_get_irq(pdev, 0); + if (davinci_ks->irq < 0) { + error = davinci_ks->irq; + goto fail2; + } + + res = platform_get_resource(pdev, IORESOURCE_MEM, 0); + if (!res) { + dev_err(dev, "no mem resource\n"); + error = -EINVAL; + goto fail2; + } + + davinci_ks->pbase = res->start; + davinci_ks->base_size = resource_size(res); + + mem = request_mem_region(davinci_ks->pbase, davinci_ks->base_size, + pdev->name); + if (!mem) { + dev_err(dev, "key scan registers at %08x are not free\n", + davinci_ks->pbase); + error = -EBUSY; + goto fail2; + } + + davinci_ks->base = ioremap(davinci_ks->pbase, davinci_ks->base_size); + if (!davinci_ks->base) { + dev_err(dev, "can't ioremap MEM resource.\n"); + error = -ENOMEM; + goto fail3; + } + + /* Enable auto repeat feature of Linux input subsystem */ + if (pdata->rep) + __set_bit(EV_REP, key_dev->evbit); + + /* Setup input device */ + __set_bit(EV_KEY, key_dev->evbit); + + /* Setup the platform data */ + davinci_ks->pdata = pdata; + + for (i = 0; i < davinci_ks->pdata->keymapsize; i++) + __set_bit(davinci_ks->pdata->keymap[i], key_dev->keybit); + + key_dev->name = "davinci_keyscan"; + key_dev->phys = "davinci_keyscan/input0"; + key_dev->dev.parent = dev; + key_dev->id.bustype = BUS_HOST; + key_dev->id.vendor = 0x0001; + key_dev->id.product = 0x0001; + key_dev->id.version = 0x0001; + key_dev->keycode = davinci_ks->keymap; + key_dev->keycodesize = sizeof(davinci_ks->keymap[0]); + key_dev->keycodemax = davinci_ks->pdata->keymapsize; + + error = input_register_device(davinci_ks->input); + if (error < 0) { + dev_err(dev, "unable to register davinci key scan device\n"); + goto fail4; + } + + error = request_irq(davinci_ks->irq, davinci_ks_interrupt, + 0, pdev->name, davinci_ks); + if (error < 0) { + dev_err(dev, "unable to register davinci key scan interrupt\n"); + goto fail5; + } + + error = davinci_ks_initialize(davinci_ks); + if (error < 0) { + dev_err(dev, "unable to initialize davinci key scan device\n"); + goto fail6; + } + + platform_set_drvdata(pdev, davinci_ks); + return 0; + +fail6: + free_irq(davinci_ks->irq, davinci_ks); +fail5: + input_unregister_device(davinci_ks->input); + key_dev = NULL; +fail4: + iounmap(davinci_ks->base); +fail3: + release_mem_region(davinci_ks->pbase, davinci_ks->base_size); +fail2: + input_free_device(key_dev); +fail1: + kfree(davinci_ks); + + return error; +} + +static int davinci_ks_remove(struct platform_device *pdev) +{ + struct davinci_ks *davinci_ks = platform_get_drvdata(pdev); + + free_irq(davinci_ks->irq, davinci_ks); + + input_unregister_device(davinci_ks->input); + + iounmap(davinci_ks->base); + release_mem_region(davinci_ks->pbase, davinci_ks->base_size); + + kfree(davinci_ks); + + return 0; +} + +static struct platform_driver davinci_ks_driver = { + .driver = { + .name = "davinci_keyscan", + }, + .remove = davinci_ks_remove, +}; + +module_platform_driver_probe(davinci_ks_driver, davinci_ks_probe); + +MODULE_AUTHOR("Miguel Aguilar"); +MODULE_DESCRIPTION("Texas Instruments DaVinci Key Scan Driver"); +MODULE_LICENSE("GPL"); |