/*
   * linux/drivers/input/keyboard/pxa27x_keypad.c
   *
   * Driver for the pxa27x matrix keyboard controller.
   *
   * Created:	Feb 22, 2007
   * Author:	Rodolfo Giometti <giometti@linux.it>
   *
   * Based on a previous implementations by Kevin O'Connor
   * <kevin_at_koconnor.net> and Alex Osborne <bobofdoom@gmail.com> and
   * on some suggestions by Nicolas Pitre <nico@fluxnic.net>.
   *
   * 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/kernel.h>
  #include <linux/module.h>
  #include <linux/interrupt.h>
  #include <linux/input.h>
  #include <linux/io.h>
  #include <linux/device.h>
  #include <linux/platform_device.h>
  #include <linux/clk.h>
  #include <linux/err.h>
  #include <linux/input/matrix_keypad.h>
  #include <linux/slab.h>
  #include <linux/of.h>
  
  #include <linux/platform_data/keypad-pxa27x.h>
  /*
   * Keypad Controller registers
   */
  #define KPC             0x0000 /* Keypad Control register */
  #define KPDK            0x0008 /* Keypad Direct Key register */
  #define KPREC           0x0010 /* Keypad Rotary Encoder register */
  #define KPMK            0x0018 /* Keypad Matrix Key register */
  #define KPAS            0x0020 /* Keypad Automatic Scan register */
  
  /* Keypad Automatic Scan Multiple Key Presser register 0-3 */
  #define KPASMKP0        0x0028
  #define KPASMKP1        0x0030
  #define KPASMKP2        0x0038
  #define KPASMKP3        0x0040
  #define KPKDI           0x0048
  
  /* bit definitions */
  #define KPC_MKRN(n)	((((n) - 1) & 0x7) << 26) /* matrix key row number */
  #define KPC_MKCN(n)	((((n) - 1) & 0x7) << 23) /* matrix key column number */
  #define KPC_DKN(n)	((((n) - 1) & 0x7) << 6)  /* direct key number */
  
  #define KPC_AS          (0x1 << 30)  /* Automatic Scan bit */
  #define KPC_ASACT       (0x1 << 29)  /* Automatic Scan on Activity */
  #define KPC_MI          (0x1 << 22)  /* Matrix interrupt bit */
  #define KPC_IMKP        (0x1 << 21)  /* Ignore Multiple Key Press */
  
  #define KPC_MS(n)	(0x1 << (13 + (n)))	/* Matrix scan line 'n' */
  #define KPC_MS_ALL      (0xff << 13)
  
  #define KPC_ME          (0x1 << 12)  /* Matrix Keypad Enable */
  #define KPC_MIE         (0x1 << 11)  /* Matrix Interrupt Enable */
  #define KPC_DK_DEB_SEL	(0x1 <<  9)  /* Direct Keypad Debounce Select */
  #define KPC_DI          (0x1 <<  5)  /* Direct key interrupt bit */
  #define KPC_RE_ZERO_DEB (0x1 <<  4)  /* Rotary Encoder Zero Debounce */
  #define KPC_REE1        (0x1 <<  3)  /* Rotary Encoder1 Enable */
  #define KPC_REE0        (0x1 <<  2)  /* Rotary Encoder0 Enable */
  #define KPC_DE          (0x1 <<  1)  /* Direct Keypad Enable */
  #define KPC_DIE         (0x1 <<  0)  /* Direct Keypad interrupt Enable */
  
  #define KPDK_DKP        (0x1 << 31)
  #define KPDK_DK(n)	((n) & 0xff)
  
  #define KPREC_OF1       (0x1 << 31)
  #define kPREC_UF1       (0x1 << 30)
  #define KPREC_OF0       (0x1 << 15)
  #define KPREC_UF0       (0x1 << 14)
  
  #define KPREC_RECOUNT0(n)	((n) & 0xff)
  #define KPREC_RECOUNT1(n)	(((n) >> 16) & 0xff)
  
  #define KPMK_MKP        (0x1 << 31)
  #define KPAS_SO         (0x1 << 31)
  #define KPASMKPx_SO     (0x1 << 31)
  
  #define KPAS_MUKP(n)	(((n) >> 26) & 0x1f)
  #define KPAS_RP(n)	(((n) >> 4) & 0xf)
  #define KPAS_CP(n)	((n) & 0xf)
  
  #define KPASMKP_MKC_MASK	(0xff)
  
  #define keypad_readl(off)	__raw_readl(keypad->mmio_base + (off))
  #define keypad_writel(off, v)	__raw_writel((v), keypad->mmio_base + (off))
  
  #define MAX_MATRIX_KEY_NUM	(MAX_MATRIX_KEY_ROWS * MAX_MATRIX_KEY_COLS)
  #define MAX_KEYPAD_KEYS		(MAX_MATRIX_KEY_NUM + MAX_DIRECT_KEY_NUM)
  
  struct pxa27x_keypad {
  	const struct pxa27x_keypad_platform_data *pdata;
  
  	struct clk *clk;
  	struct input_dev *input_dev;
  	void __iomem *mmio_base;
  
  	int irq;
  
  	unsigned short keycodes[MAX_KEYPAD_KEYS];
  	int rotary_rel_code[2];
  
  	unsigned int row_shift;
  
  	/* state row bits of each column scan */
  	uint32_t matrix_key_state[MAX_MATRIX_KEY_COLS];
  	uint32_t direct_key_state;
  
  	unsigned int direct_key_mask;
  };
  
  #ifdef CONFIG_OF
  static int pxa27x_keypad_matrix_key_parse_dt(struct pxa27x_keypad *keypad,
  				struct pxa27x_keypad_platform_data *pdata)
  {
  	struct input_dev *input_dev = keypad->input_dev;
  	struct device *dev = input_dev->dev.parent;
  	u32 rows, cols;
  	int error;
  
  	error = matrix_keypad_parse_of_params(dev, &rows, &cols);
  	if (error)
  		return error;
  
  	if (rows > MAX_MATRIX_KEY_ROWS || cols > MAX_MATRIX_KEY_COLS) {
  		dev_err(dev, "rows or cols exceeds maximum value
  ");
  		return -EINVAL;
  	}
  
  	pdata->matrix_key_rows = rows;
  	pdata->matrix_key_cols = cols;
  
  	error = matrix_keypad_build_keymap(NULL, NULL,
  					   pdata->matrix_key_rows,
  					   pdata->matrix_key_cols,
  					   keypad->keycodes, input_dev);
  	if (error)
  		return error;
  
  	return 0;
  }
  
  static int pxa27x_keypad_direct_key_parse_dt(struct pxa27x_keypad *keypad,
  				struct pxa27x_keypad_platform_data *pdata)
  {
  	struct input_dev *input_dev = keypad->input_dev;
  	struct device *dev = input_dev->dev.parent;
  	struct device_node *np = dev->of_node;
  	const __be16 *prop;
  	unsigned short code;
  	unsigned int proplen, size;
  	int i;
  	int error;
  
  	error = of_property_read_u32(np, "marvell,direct-key-count",
  				     &pdata->direct_key_num);
  	if (error) {
  		/*
  		 * If do not have marvel,direct-key-count defined,
  		 * it means direct key is not supported.
  		 */
  		return error == -EINVAL ? 0 : error;
  	}
  
  	error = of_property_read_u32(np, "marvell,direct-key-mask",
  				     &pdata->direct_key_mask);
  	if (error) {
  		if (error != -EINVAL)
  			return error;
  
  		/*
  		 * If marvell,direct-key-mask is not defined, driver will use
  		 * default value. Default value is set when configure the keypad.
  		 */
  		pdata->direct_key_mask = 0;
  	}
  
  	pdata->direct_key_low_active = of_property_read_bool(np,
  					"marvell,direct-key-low-active");
  
  	prop = of_get_property(np, "marvell,direct-key-map", &proplen);
  	if (!prop)
  		return -EINVAL;
  
  	if (proplen % sizeof(u16))
  		return -EINVAL;
  
  	size = proplen / sizeof(u16);
  
  	/* Only MAX_DIRECT_KEY_NUM is accepted.*/
  	if (size > MAX_DIRECT_KEY_NUM)
  		return -EINVAL;
  
  	for (i = 0; i < size; i++) {
  		code = be16_to_cpup(prop + i);
  		keypad->keycodes[MAX_MATRIX_KEY_NUM + i] = code;
  		__set_bit(code, input_dev->keybit);
  	}
  
  	return 0;
  }
  
  static int pxa27x_keypad_rotary_parse_dt(struct pxa27x_keypad *keypad,
  				struct pxa27x_keypad_platform_data *pdata)
  {
  	const __be32 *prop;
  	int i, relkey_ret;
  	unsigned int code, proplen;
  	const char *rotaryname[2] = {
  			"marvell,rotary0", "marvell,rotary1"};
  	const char relkeyname[] = {"marvell,rotary-rel-key"};
  	struct input_dev *input_dev = keypad->input_dev;
  	struct device *dev = input_dev->dev.parent;
  	struct device_node *np = dev->of_node;
  
  	relkey_ret = of_property_read_u32(np, relkeyname, &code);
  	/* if can read correct rotary key-code, we do not need this. */
  	if (relkey_ret == 0) {
  		unsigned short relcode;
  
  		/* rotary0 taks lower half, rotary1 taks upper half. */
  		relcode = code & 0xffff;
  		pdata->rotary0_rel_code = (code & 0xffff);
  		__set_bit(relcode, input_dev->relbit);
  
  		relcode = code >> 16;
  		pdata->rotary1_rel_code = relcode;
  		__set_bit(relcode, input_dev->relbit);
  	}
  
  	for (i = 0; i < 2; i++) {
  		prop = of_get_property(np, rotaryname[i], &proplen);
  		/*
  		 * If the prop is not set, it means keypad does not need
  		 * initialize the rotaryX.
  		 */
  		if (!prop)
  			continue;
  
  		code = be32_to_cpup(prop);
  		/*
  		 * Not all up/down key code are valid.
  		 * Now we depends on direct-rel-code.
  		 */
  		if ((!(code & 0xffff) || !(code >> 16)) && relkey_ret) {
  			return relkey_ret;
  		} else {
  			unsigned int n = MAX_MATRIX_KEY_NUM + (i << 1);
  			unsigned short keycode;
  
  			keycode = code & 0xffff;
  			keypad->keycodes[n] = keycode;
  			__set_bit(keycode, input_dev->keybit);
  
  			keycode = code >> 16;
  			keypad->keycodes[n + 1] = keycode;
  			__set_bit(keycode, input_dev->keybit);
  
  			if (i == 0)
  				pdata->rotary0_rel_code = -1;
  			else
  				pdata->rotary1_rel_code = -1;
  		}
  		if (i == 0)
  			pdata->enable_rotary0 = 1;
  		else
  			pdata->enable_rotary1 = 1;
  	}
  
  	keypad->rotary_rel_code[0] = pdata->rotary0_rel_code;
  	keypad->rotary_rel_code[1] = pdata->rotary1_rel_code;
  
  	return 0;
  }
  
  static int pxa27x_keypad_build_keycode_from_dt(struct pxa27x_keypad *keypad)
  {
  	struct input_dev *input_dev = keypad->input_dev;
  	struct device *dev = input_dev->dev.parent;
  	struct device_node *np = dev->of_node;
  	struct pxa27x_keypad_platform_data *pdata;
  	int error;
  
  	pdata = devm_kzalloc(dev, sizeof(*pdata), GFP_KERNEL);
  	if (!pdata) {
  		dev_err(dev, "failed to allocate memory for pdata
  ");
  		return -ENOMEM;
  	}
  
  	error = pxa27x_keypad_matrix_key_parse_dt(keypad, pdata);
  	if (error) {
  		dev_err(dev, "failed to parse matrix key
  ");
  		return error;
  	}
  
  	error = pxa27x_keypad_direct_key_parse_dt(keypad, pdata);
  	if (error) {
  		dev_err(dev, "failed to parse direct key
  ");
  		return error;
  	}
  
  	error = pxa27x_keypad_rotary_parse_dt(keypad, pdata);
  	if (error) {
  		dev_err(dev, "failed to parse rotary key
  ");
  		return error;
  	}
  
  	error = of_property_read_u32(np, "marvell,debounce-interval",
  				     &pdata->debounce_interval);
  	if (error) {
  		dev_err(dev, "failed to parse debpunce-interval
  ");
  		return error;
  	}
  
  	/*
  	 * The keycodes may not only includes matrix key but also the direct
  	 * key or rotary key.
  	 */
  	input_dev->keycodemax = ARRAY_SIZE(keypad->keycodes);
  
  	keypad->pdata = pdata;
  	return 0;
  }
  
  #else
  
  static int pxa27x_keypad_build_keycode_from_dt(struct pxa27x_keypad *keypad)
  {
  	dev_info(keypad->input_dev->dev.parent, "missing platform data
  ");
  
  	return -EINVAL;
  }
  
  #endif
  
  static int pxa27x_keypad_build_keycode(struct pxa27x_keypad *keypad)
  {
  	const struct pxa27x_keypad_platform_data *pdata = keypad->pdata;
  	struct input_dev *input_dev = keypad->input_dev;
  	unsigned short keycode;
  	int i;
  	int error;
  
  	error = matrix_keypad_build_keymap(pdata->matrix_keymap_data, NULL,
  					   pdata->matrix_key_rows,
  					   pdata->matrix_key_cols,
  					   keypad->keycodes, input_dev);
  	if (error)
  		return error;
  
  	/*
  	 * The keycodes may not only include matrix keys but also the direct
  	 * or rotary keys.
  	 */
  	input_dev->keycodemax = ARRAY_SIZE(keypad->keycodes);
  
  	/* For direct keys. */
  	for (i = 0; i < pdata->direct_key_num; i++) {
  		keycode = pdata->direct_key_map[i];
  		keypad->keycodes[MAX_MATRIX_KEY_NUM + i] = keycode;
  		__set_bit(keycode, input_dev->keybit);
  	}
  
  	if (pdata->enable_rotary0) {
  		if (pdata->rotary0_up_key && pdata->rotary0_down_key) {
  			keycode = pdata->rotary0_up_key;
  			keypad->keycodes[MAX_MATRIX_KEY_NUM + 0] = keycode;
  			__set_bit(keycode, input_dev->keybit);
  
  			keycode = pdata->rotary0_down_key;
  			keypad->keycodes[MAX_MATRIX_KEY_NUM + 1] = keycode;
  			__set_bit(keycode, input_dev->keybit);
  
  			keypad->rotary_rel_code[0] = -1;
  		} else {
  			keypad->rotary_rel_code[0] = pdata->rotary0_rel_code;
  			__set_bit(pdata->rotary0_rel_code, input_dev->relbit);
  		}
  	}
  
  	if (pdata->enable_rotary1) {
  		if (pdata->rotary1_up_key && pdata->rotary1_down_key) {
  			keycode = pdata->rotary1_up_key;
  			keypad->keycodes[MAX_MATRIX_KEY_NUM + 2] = keycode;
  			__set_bit(keycode, input_dev->keybit);
  
  			keycode = pdata->rotary1_down_key;
  			keypad->keycodes[MAX_MATRIX_KEY_NUM + 3] = keycode;
  			__set_bit(keycode, input_dev->keybit);
  
  			keypad->rotary_rel_code[1] = -1;
  		} else {
  			keypad->rotary_rel_code[1] = pdata->rotary1_rel_code;
  			__set_bit(pdata->rotary1_rel_code, input_dev->relbit);
  		}
  	}
  
  	__clear_bit(KEY_RESERVED, input_dev->keybit);
  
  	return 0;
  }
  
  static void pxa27x_keypad_scan_matrix(struct pxa27x_keypad *keypad)
  {
  	const struct pxa27x_keypad_platform_data *pdata = keypad->pdata;
  	struct input_dev *input_dev = keypad->input_dev;
  	int row, col, num_keys_pressed = 0;
  	uint32_t new_state[MAX_MATRIX_KEY_COLS];
  	uint32_t kpas = keypad_readl(KPAS);
  
  	num_keys_pressed = KPAS_MUKP(kpas);
  
  	memset(new_state, 0, sizeof(new_state));
  
  	if (num_keys_pressed == 0)
  		goto scan;
  
  	if (num_keys_pressed == 1) {
  		col = KPAS_CP(kpas);
  		row = KPAS_RP(kpas);
  
  		/* if invalid row/col, treat as no key pressed */
  		if (col >= pdata->matrix_key_cols ||
  		    row >= pdata->matrix_key_rows)
  			goto scan;
  
  		new_state[col] = (1 << row);
  		goto scan;
  	}
  
  	if (num_keys_pressed > 1) {
  		uint32_t kpasmkp0 = keypad_readl(KPASMKP0);
  		uint32_t kpasmkp1 = keypad_readl(KPASMKP1);
  		uint32_t kpasmkp2 = keypad_readl(KPASMKP2);
  		uint32_t kpasmkp3 = keypad_readl(KPASMKP3);
  
  		new_state[0] = kpasmkp0 & KPASMKP_MKC_MASK;
  		new_state[1] = (kpasmkp0 >> 16) & KPASMKP_MKC_MASK;
  		new_state[2] = kpasmkp1 & KPASMKP_MKC_MASK;
  		new_state[3] = (kpasmkp1 >> 16) & KPASMKP_MKC_MASK;
  		new_state[4] = kpasmkp2 & KPASMKP_MKC_MASK;
  		new_state[5] = (kpasmkp2 >> 16) & KPASMKP_MKC_MASK;
  		new_state[6] = kpasmkp3 & KPASMKP_MKC_MASK;
  		new_state[7] = (kpasmkp3 >> 16) & KPASMKP_MKC_MASK;
  	}
  scan:
  	for (col = 0; col < pdata->matrix_key_cols; col++) {
  		uint32_t bits_changed;
  		int code;
  
  		bits_changed = keypad->matrix_key_state[col] ^ new_state[col];
  		if (bits_changed == 0)
  			continue;
  
  		for (row = 0; row < pdata->matrix_key_rows; row++) {
  			if ((bits_changed & (1 << row)) == 0)
  				continue;
  
  			code = MATRIX_SCAN_CODE(row, col, keypad->row_shift);
  
  			input_event(input_dev, EV_MSC, MSC_SCAN, code);
  			input_report_key(input_dev, keypad->keycodes[code],
  					 new_state[col] & (1 << row));
  		}
  	}
  	input_sync(input_dev);
  	memcpy(keypad->matrix_key_state, new_state, sizeof(new_state));
  }
  
  #define DEFAULT_KPREC	(0x007f007f)
  
  static inline int rotary_delta(uint32_t kprec)
  {
  	if (kprec & KPREC_OF0)
  		return (kprec & 0xff) + 0x7f;
  	else if (kprec & KPREC_UF0)
  		return (kprec & 0xff) - 0x7f - 0xff;
  	else
  		return (kprec & 0xff) - 0x7f;
  }
  
  static void report_rotary_event(struct pxa27x_keypad *keypad, int r, int delta)
  {
  	struct input_dev *dev = keypad->input_dev;
  
  	if (delta == 0)
  		return;
  
  	if (keypad->rotary_rel_code[r] == -1) {
  		int code = MAX_MATRIX_KEY_NUM + 2 * r + (delta > 0 ? 0 : 1);
  		unsigned char keycode = keypad->keycodes[code];
  
  		/* simulate a press-n-release */
  		input_event(dev, EV_MSC, MSC_SCAN, code);
  		input_report_key(dev, keycode, 1);
  		input_sync(dev);
  		input_event(dev, EV_MSC, MSC_SCAN, code);
  		input_report_key(dev, keycode, 0);
  		input_sync(dev);
  	} else {
  		input_report_rel(dev, keypad->rotary_rel_code[r], delta);
  		input_sync(dev);
  	}
  }
  
  static void pxa27x_keypad_scan_rotary(struct pxa27x_keypad *keypad)
  {
  	const struct pxa27x_keypad_platform_data *pdata = keypad->pdata;
  	uint32_t kprec;
  
  	/* read and reset to default count value */
  	kprec = keypad_readl(KPREC);
  	keypad_writel(KPREC, DEFAULT_KPREC);
  
  	if (pdata->enable_rotary0)
  		report_rotary_event(keypad, 0, rotary_delta(kprec));
  
  	if (pdata->enable_rotary1)
  		report_rotary_event(keypad, 1, rotary_delta(kprec >> 16));
  }
  
  static void pxa27x_keypad_scan_direct(struct pxa27x_keypad *keypad)
  {
  	const struct pxa27x_keypad_platform_data *pdata = keypad->pdata;
  	struct input_dev *input_dev = keypad->input_dev;
  	unsigned int new_state;
  	uint32_t kpdk, bits_changed;
  	int i;
  
  	kpdk = keypad_readl(KPDK);
  
  	if (pdata->enable_rotary0 || pdata->enable_rotary1)
  		pxa27x_keypad_scan_rotary(keypad);
  
  	/*
  	 * The KPDR_DK only output the key pin level, so it relates to board,
  	 * and low level may be active.
  	 */
  	if (pdata->direct_key_low_active)
  		new_state = ~KPDK_DK(kpdk) & keypad->direct_key_mask;
  	else
  		new_state = KPDK_DK(kpdk) & keypad->direct_key_mask;
  
  	bits_changed = keypad->direct_key_state ^ new_state;
  
  	if (bits_changed == 0)
  		return;
  
  	for (i = 0; i < pdata->direct_key_num; i++) {
  		if (bits_changed & (1 << i)) {
  			int code = MAX_MATRIX_KEY_NUM + i;
  
  			input_event(input_dev, EV_MSC, MSC_SCAN, code);
  			input_report_key(input_dev, keypad->keycodes[code],
  					 new_state & (1 << i));
  		}
  	}
  	input_sync(input_dev);
  	keypad->direct_key_state = new_state;
  }
  
  static void clear_wakeup_event(struct pxa27x_keypad *keypad)
  {
  	const struct pxa27x_keypad_platform_data *pdata = keypad->pdata;
  
  	if (pdata->clear_wakeup_event)
  		(pdata->clear_wakeup_event)();
  }
  
  static irqreturn_t pxa27x_keypad_irq_handler(int irq, void *dev_id)
  {
  	struct pxa27x_keypad *keypad = dev_id;
  	unsigned long kpc = keypad_readl(KPC);
  
  	clear_wakeup_event(keypad);
  
  	if (kpc & KPC_DI)
  		pxa27x_keypad_scan_direct(keypad);
  
  	if (kpc & KPC_MI)
  		pxa27x_keypad_scan_matrix(keypad);
  
  	return IRQ_HANDLED;
  }
  
  static void pxa27x_keypad_config(struct pxa27x_keypad *keypad)
  {
  	const struct pxa27x_keypad_platform_data *pdata = keypad->pdata;
  	unsigned int mask = 0, direct_key_num = 0;
  	unsigned long kpc = 0;
  
  	/* clear pending interrupt bit */
  	keypad_readl(KPC);
  
  	/* enable matrix keys with automatic scan */
  	if (pdata->matrix_key_rows && pdata->matrix_key_cols) {
  		kpc |= KPC_ASACT | KPC_MIE | KPC_ME | KPC_MS_ALL;
  		kpc |= KPC_MKRN(pdata->matrix_key_rows) |
  		       KPC_MKCN(pdata->matrix_key_cols);
  	}
  
  	/* enable rotary key, debounce interval same as direct keys */
  	if (pdata->enable_rotary0) {
  		mask |= 0x03;
  		direct_key_num = 2;
  		kpc |= KPC_REE0;
  	}
  
  	if (pdata->enable_rotary1) {
  		mask |= 0x0c;
  		direct_key_num = 4;
  		kpc |= KPC_REE1;
  	}
  
  	if (pdata->direct_key_num > direct_key_num)
  		direct_key_num = pdata->direct_key_num;
  
  	/*
  	 * Direct keys usage may not start from KP_DKIN0, check the platfrom
  	 * mask data to config the specific.
  	 */
  	if (pdata->direct_key_mask)
  		keypad->direct_key_mask = pdata->direct_key_mask;
  	else
  		keypad->direct_key_mask = ((1 << direct_key_num) - 1) & ~mask;
  
  	/* enable direct key */
  	if (direct_key_num)
  		kpc |= KPC_DE | KPC_DIE | KPC_DKN(direct_key_num);
  
  	keypad_writel(KPC, kpc | KPC_RE_ZERO_DEB);
  	keypad_writel(KPREC, DEFAULT_KPREC);
  	keypad_writel(KPKDI, pdata->debounce_interval);
  }
  
  static int pxa27x_keypad_open(struct input_dev *dev)
  {
  	struct pxa27x_keypad *keypad = input_get_drvdata(dev);
  
  	/* Enable unit clock */
  	clk_prepare_enable(keypad->clk);
  	pxa27x_keypad_config(keypad);
  
  	return 0;
  }
  
  static void pxa27x_keypad_close(struct input_dev *dev)
  {
  	struct pxa27x_keypad *keypad = input_get_drvdata(dev);
  
  	/* Disable clock unit */
  	clk_disable_unprepare(keypad->clk);
  }
  
  #ifdef CONFIG_PM_SLEEP
  static int pxa27x_keypad_suspend(struct device *dev)
  {
  	struct platform_device *pdev = to_platform_device(dev);
  	struct pxa27x_keypad *keypad = platform_get_drvdata(pdev);
  
  	/*
  	 * If the keypad is used a wake up source, clock can not be disabled.
  	 * Or it can not detect the key pressing.
  	 */
  	if (device_may_wakeup(&pdev->dev))
  		enable_irq_wake(keypad->irq);
  	else
  		clk_disable_unprepare(keypad->clk);
  
  	return 0;
  }
  
  static int pxa27x_keypad_resume(struct device *dev)
  {
  	struct platform_device *pdev = to_platform_device(dev);
  	struct pxa27x_keypad *keypad = platform_get_drvdata(pdev);
  	struct input_dev *input_dev = keypad->input_dev;
  
  	/*
  	 * If the keypad is used as wake up source, the clock is not turned
  	 * off. So do not need configure it again.
  	 */
  	if (device_may_wakeup(&pdev->dev)) {
  		disable_irq_wake(keypad->irq);
  	} else {
  		mutex_lock(&input_dev->mutex);
  
  		if (input_dev->users) {
  			/* Enable unit clock */
  			clk_prepare_enable(keypad->clk);
  			pxa27x_keypad_config(keypad);
  		}
  
  		mutex_unlock(&input_dev->mutex);
  	}
  
  	return 0;
  }
  #endif
  
  static SIMPLE_DEV_PM_OPS(pxa27x_keypad_pm_ops,
  			 pxa27x_keypad_suspend, pxa27x_keypad_resume);
  
  
  static int pxa27x_keypad_probe(struct platform_device *pdev)
  {
  	const struct pxa27x_keypad_platform_data *pdata =
  					dev_get_platdata(&pdev->dev);
  	struct device_node *np = pdev->dev.of_node;
  	struct pxa27x_keypad *keypad;
  	struct input_dev *input_dev;
  	struct resource *res;
  	int irq, error;
  
  	/* Driver need build keycode from device tree or pdata */
  	if (!np && !pdata)
  		return -EINVAL;
  
  	irq = platform_get_irq(pdev, 0);
  	if (irq < 0) {
  		dev_err(&pdev->dev, "failed to get keypad irq
  ");
  		return -ENXIO;
  	}
  
  	res = platform_get_resource(pdev, IORESOURCE_MEM, 0);
  	if (res == NULL) {
  		dev_err(&pdev->dev, "failed to get I/O memory
  ");
  		return -ENXIO;
  	}
  
  	keypad = devm_kzalloc(&pdev->dev, sizeof(*keypad),
  			      GFP_KERNEL);
  	if (!keypad)
  		return -ENOMEM;
  
  	input_dev = devm_input_allocate_device(&pdev->dev);
  	if (!input_dev)
  		return -ENOMEM;
  
  	keypad->pdata = pdata;
  	keypad->input_dev = input_dev;
  	keypad->irq = irq;
  
  	keypad->mmio_base = devm_ioremap_resource(&pdev->dev, res);
  	if (IS_ERR(keypad->mmio_base))
  		return PTR_ERR(keypad->mmio_base);
  
  	keypad->clk = devm_clk_get(&pdev->dev, NULL);
  	if (IS_ERR(keypad->clk)) {
  		dev_err(&pdev->dev, "failed to get keypad clock
  ");
  		return PTR_ERR(keypad->clk);
  	}
  
  	input_dev->name = pdev->name;
  	input_dev->id.bustype = BUS_HOST;
  	input_dev->open = pxa27x_keypad_open;
  	input_dev->close = pxa27x_keypad_close;
  	input_dev->dev.parent = &pdev->dev;
  
  	input_dev->keycode = keypad->keycodes;
  	input_dev->keycodesize = sizeof(keypad->keycodes[0]);
  	input_dev->keycodemax = ARRAY_SIZE(keypad->keycodes);
  
  	input_set_drvdata(input_dev, keypad);
  
  	input_dev->evbit[0] = BIT_MASK(EV_KEY) | BIT_MASK(EV_REP);
  	input_set_capability(input_dev, EV_MSC, MSC_SCAN);
  
  	if (pdata) {
  		error = pxa27x_keypad_build_keycode(keypad);
  	} else {
  		error = pxa27x_keypad_build_keycode_from_dt(keypad);
  		/*
  		 * Data that we get from DT resides in dynamically
  		 * allocated memory so we need to update our pdata
  		 * pointer.
  		 */
  		pdata = keypad->pdata;
  	}
  	if (error) {
  		dev_err(&pdev->dev, "failed to build keycode
  ");
  		return error;
  	}
  
  	keypad->row_shift = get_count_order(pdata->matrix_key_cols);
  
  	if ((pdata->enable_rotary0 && keypad->rotary_rel_code[0] != -1) ||
  	    (pdata->enable_rotary1 && keypad->rotary_rel_code[1] != -1)) {
  		input_dev->evbit[0] |= BIT_MASK(EV_REL);
  	}
  
  	error = devm_request_irq(&pdev->dev, irq, pxa27x_keypad_irq_handler,
  				 0, pdev->name, keypad);
  	if (error) {
  		dev_err(&pdev->dev, "failed to request IRQ
  ");
  		return error;
  	}
  
  	/* Register the input device */
  	error = input_register_device(input_dev);
  	if (error) {
  		dev_err(&pdev->dev, "failed to register input device
  ");
  		return error;
  	}
  
  	platform_set_drvdata(pdev, keypad);
  	device_init_wakeup(&pdev->dev, 1);
  
  	return 0;
  }
  
  #ifdef CONFIG_OF
  static const struct of_device_id pxa27x_keypad_dt_match[] = {
  	{ .compatible = "marvell,pxa27x-keypad" },
  	{},
  };
  MODULE_DEVICE_TABLE(of, pxa27x_keypad_dt_match);
  #endif
  
  static struct platform_driver pxa27x_keypad_driver = {
  	.probe		= pxa27x_keypad_probe,
  	.driver		= {
  		.name	= "pxa27x-keypad",
  		.of_match_table = of_match_ptr(pxa27x_keypad_dt_match),
  		.pm	= &pxa27x_keypad_pm_ops,
  	},
  };
  module_platform_driver(pxa27x_keypad_driver);
  
  MODULE_DESCRIPTION("PXA27x Keypad Controller Driver");
  MODULE_LICENSE("GPL");
  /* work with hotplug and coldplug */
  MODULE_ALIAS("platform:pxa27x-keypad");