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v4.6
 
  1/*
  2 * Keyboard class input driver for the NVIDIA Tegra SoC internal matrix
  3 * keyboard controller
  4 *
  5 * Copyright (c) 2009-2011, NVIDIA Corporation.
  6 *
  7 * This program is free software; you can redistribute it and/or modify
  8 * it under the terms of the GNU General Public License as published by
  9 * the Free Software Foundation; either version 2 of the License, or
 10 * (at your option) any later version.
 11 *
 12 * This program is distributed in the hope that it will be useful, but WITHOUT
 13 * ANY WARRANTY; without even the implied warranty of MERCHANTABILITY or
 14 * FITNESS FOR A PARTICULAR PURPOSE.  See the GNU General Public License for
 15 * more details.
 16 *
 17 * You should have received a copy of the GNU General Public License along
 18 * with this program; if not, write to the Free Software Foundation, Inc.,
 19 * 51 Franklin Street, Fifth Floor, Boston, MA  02110-1301, USA.
 20 */
 21
 22#include <linux/kernel.h>
 23#include <linux/module.h>
 24#include <linux/input.h>
 25#include <linux/platform_device.h>
 26#include <linux/delay.h>
 27#include <linux/io.h>
 28#include <linux/interrupt.h>
 29#include <linux/of.h>
 30#include <linux/of_device.h>
 31#include <linux/clk.h>
 32#include <linux/slab.h>
 33#include <linux/input/matrix_keypad.h>
 34#include <linux/reset.h>
 35#include <linux/err.h>
 36
 37#define KBC_MAX_KPENT	8
 38
 39/* Maximum row/column supported by Tegra KBC yet  is 16x8 */
 40#define KBC_MAX_GPIO	24
 41/* Maximum keys supported by Tegra KBC yet is 16 x 8*/
 42#define KBC_MAX_KEY	(16 * 8)
 43
 44#define KBC_MAX_DEBOUNCE_CNT	0x3ffu
 45
 46/* KBC row scan time and delay for beginning the row scan. */
 47#define KBC_ROW_SCAN_TIME	16
 48#define KBC_ROW_SCAN_DLY	5
 49
 50/* KBC uses a 32KHz clock so a cycle = 1/32Khz */
 51#define KBC_CYCLE_MS	32
 52
 53/* KBC Registers */
 54
 55/* KBC Control Register */
 56#define KBC_CONTROL_0	0x0
 57#define KBC_FIFO_TH_CNT_SHIFT(cnt)	(cnt << 14)
 58#define KBC_DEBOUNCE_CNT_SHIFT(cnt)	(cnt << 4)
 59#define KBC_CONTROL_FIFO_CNT_INT_EN	(1 << 3)
 60#define KBC_CONTROL_KEYPRESS_INT_EN	(1 << 1)
 61#define KBC_CONTROL_KBC_EN		(1 << 0)
 62
 63/* KBC Interrupt Register */
 64#define KBC_INT_0	0x4
 65#define KBC_INT_FIFO_CNT_INT_STATUS	(1 << 2)
 66#define KBC_INT_KEYPRESS_INT_STATUS	(1 << 0)
 67
 68#define KBC_ROW_CFG0_0	0x8
 69#define KBC_COL_CFG0_0	0x18
 70#define KBC_TO_CNT_0	0x24
 71#define KBC_INIT_DLY_0	0x28
 72#define KBC_RPT_DLY_0	0x2c
 73#define KBC_KP_ENT0_0	0x30
 74#define KBC_KP_ENT1_0	0x34
 75#define KBC_ROW0_MASK_0	0x38
 76
 77#define KBC_ROW_SHIFT	3
 78
 79enum tegra_pin_type {
 80	PIN_CFG_IGNORE,
 81	PIN_CFG_COL,
 82	PIN_CFG_ROW,
 83};
 84
 85/* Tegra KBC hw support */
 86struct tegra_kbc_hw_support {
 87	int max_rows;
 88	int max_columns;
 89};
 90
 91struct tegra_kbc_pin_cfg {
 92	enum tegra_pin_type type;
 93	unsigned char num;
 94};
 95
 96struct tegra_kbc {
 97	struct device *dev;
 98	unsigned int debounce_cnt;
 99	unsigned int repeat_cnt;
100	struct tegra_kbc_pin_cfg pin_cfg[KBC_MAX_GPIO];
101	const struct matrix_keymap_data *keymap_data;
102	bool wakeup;
103	void __iomem *mmio;
104	struct input_dev *idev;
105	int irq;
106	spinlock_t lock;
107	unsigned int repoll_dly;
108	unsigned long cp_dly_jiffies;
109	unsigned int cp_to_wkup_dly;
110	bool use_fn_map;
111	bool use_ghost_filter;
112	bool keypress_caused_wake;
113	unsigned short keycode[KBC_MAX_KEY * 2];
114	unsigned short current_keys[KBC_MAX_KPENT];
115	unsigned int num_pressed_keys;
116	u32 wakeup_key;
117	struct timer_list timer;
118	struct clk *clk;
119	struct reset_control *rst;
120	const struct tegra_kbc_hw_support *hw_support;
121	int max_keys;
122	int num_rows_and_columns;
123};
124
125static void tegra_kbc_report_released_keys(struct input_dev *input,
126					   unsigned short old_keycodes[],
127					   unsigned int old_num_keys,
128					   unsigned short new_keycodes[],
129					   unsigned int new_num_keys)
130{
131	unsigned int i, j;
132
133	for (i = 0; i < old_num_keys; i++) {
134		for (j = 0; j < new_num_keys; j++)
135			if (old_keycodes[i] == new_keycodes[j])
136				break;
137
138		if (j == new_num_keys)
139			input_report_key(input, old_keycodes[i], 0);
140	}
141}
142
143static void tegra_kbc_report_pressed_keys(struct input_dev *input,
144					  unsigned char scancodes[],
145					  unsigned short keycodes[],
146					  unsigned int num_pressed_keys)
147{
148	unsigned int i;
149
150	for (i = 0; i < num_pressed_keys; i++) {
151		input_event(input, EV_MSC, MSC_SCAN, scancodes[i]);
152		input_report_key(input, keycodes[i], 1);
153	}
154}
155
156static void tegra_kbc_report_keys(struct tegra_kbc *kbc)
157{
158	unsigned char scancodes[KBC_MAX_KPENT];
159	unsigned short keycodes[KBC_MAX_KPENT];
160	u32 val = 0;
161	unsigned int i;
162	unsigned int num_down = 0;
163	bool fn_keypress = false;
164	bool key_in_same_row = false;
165	bool key_in_same_col = false;
166
167	for (i = 0; i < KBC_MAX_KPENT; i++) {
168		if ((i % 4) == 0)
169			val = readl(kbc->mmio + KBC_KP_ENT0_0 + i);
170
171		if (val & 0x80) {
172			unsigned int col = val & 0x07;
173			unsigned int row = (val >> 3) & 0x0f;
174			unsigned char scancode =
175				MATRIX_SCAN_CODE(row, col, KBC_ROW_SHIFT);
176
177			scancodes[num_down] = scancode;
178			keycodes[num_down] = kbc->keycode[scancode];
179			/* If driver uses Fn map, do not report the Fn key. */
180			if ((keycodes[num_down] == KEY_FN) && kbc->use_fn_map)
181				fn_keypress = true;
182			else
183				num_down++;
184		}
185
186		val >>= 8;
187	}
188
189	/*
190	 * Matrix keyboard designs are prone to keyboard ghosting.
191	 * Ghosting occurs if there are 3 keys such that -
192	 * any 2 of the 3 keys share a row, and any 2 of them share a column.
193	 * If so ignore the key presses for this iteration.
194	 */
195	if (kbc->use_ghost_filter && num_down >= 3) {
196		for (i = 0; i < num_down; i++) {
197			unsigned int j;
198			u8 curr_col = scancodes[i] & 0x07;
199			u8 curr_row = scancodes[i] >> KBC_ROW_SHIFT;
200
201			/*
202			 * Find 2 keys such that one key is in the same row
203			 * and the other is in the same column as the i-th key.
204			 */
205			for (j = i + 1; j < num_down; j++) {
206				u8 col = scancodes[j] & 0x07;
207				u8 row = scancodes[j] >> KBC_ROW_SHIFT;
208
209				if (col == curr_col)
210					key_in_same_col = true;
211				if (row == curr_row)
212					key_in_same_row = true;
213			}
214		}
215	}
216
217	/*
218	 * If the platform uses Fn keymaps, translate keys on a Fn keypress.
219	 * Function keycodes are max_keys apart from the plain keycodes.
220	 */
221	if (fn_keypress) {
222		for (i = 0; i < num_down; i++) {
223			scancodes[i] += kbc->max_keys;
224			keycodes[i] = kbc->keycode[scancodes[i]];
225		}
226	}
227
228	/* Ignore the key presses for this iteration? */
229	if (key_in_same_col && key_in_same_row)
230		return;
231
232	tegra_kbc_report_released_keys(kbc->idev,
233				       kbc->current_keys, kbc->num_pressed_keys,
234				       keycodes, num_down);
235	tegra_kbc_report_pressed_keys(kbc->idev, scancodes, keycodes, num_down);
236	input_sync(kbc->idev);
237
238	memcpy(kbc->current_keys, keycodes, sizeof(kbc->current_keys));
239	kbc->num_pressed_keys = num_down;
240}
241
242static void tegra_kbc_set_fifo_interrupt(struct tegra_kbc *kbc, bool enable)
243{
244	u32 val;
245
246	val = readl(kbc->mmio + KBC_CONTROL_0);
247	if (enable)
248		val |= KBC_CONTROL_FIFO_CNT_INT_EN;
249	else
250		val &= ~KBC_CONTROL_FIFO_CNT_INT_EN;
251	writel(val, kbc->mmio + KBC_CONTROL_0);
252}
253
254static void tegra_kbc_keypress_timer(unsigned long data)
255{
256	struct tegra_kbc *kbc = (struct tegra_kbc *)data;
257	unsigned long flags;
258	u32 val;
259	unsigned int i;
260
261	spin_lock_irqsave(&kbc->lock, flags);
262
263	val = (readl(kbc->mmio + KBC_INT_0) >> 4) & 0xf;
264	if (val) {
265		unsigned long dly;
266
267		tegra_kbc_report_keys(kbc);
268
269		/*
270		 * If more than one keys are pressed we need not wait
271		 * for the repoll delay.
272		 */
273		dly = (val == 1) ? kbc->repoll_dly : 1;
274		mod_timer(&kbc->timer, jiffies + msecs_to_jiffies(dly));
275	} else {
276		/* Release any pressed keys and exit the polling loop */
277		for (i = 0; i < kbc->num_pressed_keys; i++)
278			input_report_key(kbc->idev, kbc->current_keys[i], 0);
279		input_sync(kbc->idev);
280
281		kbc->num_pressed_keys = 0;
282
283		/* All keys are released so enable the keypress interrupt */
284		tegra_kbc_set_fifo_interrupt(kbc, true);
285	}
286
287	spin_unlock_irqrestore(&kbc->lock, flags);
288}
289
290static irqreturn_t tegra_kbc_isr(int irq, void *args)
291{
292	struct tegra_kbc *kbc = args;
293	unsigned long flags;
294	u32 val;
295
296	spin_lock_irqsave(&kbc->lock, flags);
297
298	/*
299	 * Quickly bail out & reenable interrupts if the fifo threshold
300	 * count interrupt wasn't the interrupt source
301	 */
302	val = readl(kbc->mmio + KBC_INT_0);
303	writel(val, kbc->mmio + KBC_INT_0);
304
305	if (val & KBC_INT_FIFO_CNT_INT_STATUS) {
306		/*
307		 * Until all keys are released, defer further processing to
308		 * the polling loop in tegra_kbc_keypress_timer.
309		 */
310		tegra_kbc_set_fifo_interrupt(kbc, false);
311		mod_timer(&kbc->timer, jiffies + kbc->cp_dly_jiffies);
312	} else if (val & KBC_INT_KEYPRESS_INT_STATUS) {
313		/* We can be here only through system resume path */
314		kbc->keypress_caused_wake = true;
315	}
316
317	spin_unlock_irqrestore(&kbc->lock, flags);
318
319	return IRQ_HANDLED;
320}
321
322static void tegra_kbc_setup_wakekeys(struct tegra_kbc *kbc, bool filter)
323{
324	int i;
325	unsigned int rst_val;
326
327	/* Either mask all keys or none. */
328	rst_val = (filter && !kbc->wakeup) ? ~0 : 0;
329
330	for (i = 0; i < kbc->hw_support->max_rows; i++)
331		writel(rst_val, kbc->mmio + KBC_ROW0_MASK_0 + i * 4);
332}
333
334static void tegra_kbc_config_pins(struct tegra_kbc *kbc)
335{
336	int i;
337
338	for (i = 0; i < KBC_MAX_GPIO; i++) {
339		u32 r_shft = 5 * (i % 6);
340		u32 c_shft = 4 * (i % 8);
341		u32 r_mask = 0x1f << r_shft;
342		u32 c_mask = 0x0f << c_shft;
343		u32 r_offs = (i / 6) * 4 + KBC_ROW_CFG0_0;
344		u32 c_offs = (i / 8) * 4 + KBC_COL_CFG0_0;
345		u32 row_cfg = readl(kbc->mmio + r_offs);
346		u32 col_cfg = readl(kbc->mmio + c_offs);
347
348		row_cfg &= ~r_mask;
349		col_cfg &= ~c_mask;
350
351		switch (kbc->pin_cfg[i].type) {
352		case PIN_CFG_ROW:
353			row_cfg |= ((kbc->pin_cfg[i].num << 1) | 1) << r_shft;
354			break;
355
356		case PIN_CFG_COL:
357			col_cfg |= ((kbc->pin_cfg[i].num << 1) | 1) << c_shft;
358			break;
359
360		case PIN_CFG_IGNORE:
361			break;
362		}
363
364		writel(row_cfg, kbc->mmio + r_offs);
365		writel(col_cfg, kbc->mmio + c_offs);
366	}
367}
368
369static int tegra_kbc_start(struct tegra_kbc *kbc)
370{
371	unsigned int debounce_cnt;
372	u32 val = 0;
 
373
374	clk_prepare_enable(kbc->clk);
 
 
375
376	/* Reset the KBC controller to clear all previous status.*/
377	reset_control_assert(kbc->rst);
378	udelay(100);
379	reset_control_assert(kbc->rst);
380	udelay(100);
381
382	tegra_kbc_config_pins(kbc);
383	tegra_kbc_setup_wakekeys(kbc, false);
384
385	writel(kbc->repeat_cnt, kbc->mmio + KBC_RPT_DLY_0);
386
387	/* Keyboard debounce count is maximum of 12 bits. */
388	debounce_cnt = min(kbc->debounce_cnt, KBC_MAX_DEBOUNCE_CNT);
389	val = KBC_DEBOUNCE_CNT_SHIFT(debounce_cnt);
390	val |= KBC_FIFO_TH_CNT_SHIFT(1); /* set fifo interrupt threshold to 1 */
391	val |= KBC_CONTROL_FIFO_CNT_INT_EN;  /* interrupt on FIFO threshold */
392	val |= KBC_CONTROL_KBC_EN;     /* enable */
393	writel(val, kbc->mmio + KBC_CONTROL_0);
394
395	/*
396	 * Compute the delay(ns) from interrupt mode to continuous polling
397	 * mode so the timer routine is scheduled appropriately.
398	 */
399	val = readl(kbc->mmio + KBC_INIT_DLY_0);
400	kbc->cp_dly_jiffies = usecs_to_jiffies((val & 0xfffff) * 32);
401
402	kbc->num_pressed_keys = 0;
403
404	/*
405	 * Atomically clear out any remaining entries in the key FIFO
406	 * and enable keyboard interrupts.
407	 */
408	while (1) {
409		val = readl(kbc->mmio + KBC_INT_0);
410		val >>= 4;
411		if (!val)
412			break;
413
414		val = readl(kbc->mmio + KBC_KP_ENT0_0);
415		val = readl(kbc->mmio + KBC_KP_ENT1_0);
416	}
417	writel(0x7, kbc->mmio + KBC_INT_0);
418
419	enable_irq(kbc->irq);
420
421	return 0;
422}
423
424static void tegra_kbc_stop(struct tegra_kbc *kbc)
425{
426	unsigned long flags;
427	u32 val;
428
429	spin_lock_irqsave(&kbc->lock, flags);
430	val = readl(kbc->mmio + KBC_CONTROL_0);
431	val &= ~1;
432	writel(val, kbc->mmio + KBC_CONTROL_0);
433	spin_unlock_irqrestore(&kbc->lock, flags);
434
435	disable_irq(kbc->irq);
436	del_timer_sync(&kbc->timer);
437
438	clk_disable_unprepare(kbc->clk);
439}
440
441static int tegra_kbc_open(struct input_dev *dev)
442{
443	struct tegra_kbc *kbc = input_get_drvdata(dev);
444
445	return tegra_kbc_start(kbc);
446}
447
448static void tegra_kbc_close(struct input_dev *dev)
449{
450	struct tegra_kbc *kbc = input_get_drvdata(dev);
451
452	return tegra_kbc_stop(kbc);
453}
454
455static bool tegra_kbc_check_pin_cfg(const struct tegra_kbc *kbc,
456					unsigned int *num_rows)
457{
458	int i;
459
460	*num_rows = 0;
461
462	for (i = 0; i < KBC_MAX_GPIO; i++) {
463		const struct tegra_kbc_pin_cfg *pin_cfg = &kbc->pin_cfg[i];
464
465		switch (pin_cfg->type) {
466		case PIN_CFG_ROW:
467			if (pin_cfg->num >= kbc->hw_support->max_rows) {
468				dev_err(kbc->dev,
469					"pin_cfg[%d]: invalid row number %d\n",
470					i, pin_cfg->num);
471				return false;
472			}
473			(*num_rows)++;
474			break;
475
476		case PIN_CFG_COL:
477			if (pin_cfg->num >= kbc->hw_support->max_columns) {
478				dev_err(kbc->dev,
479					"pin_cfg[%d]: invalid column number %d\n",
480					i, pin_cfg->num);
481				return false;
482			}
483			break;
484
485		case PIN_CFG_IGNORE:
486			break;
487
488		default:
489			dev_err(kbc->dev,
490				"pin_cfg[%d]: invalid entry type %d\n",
491				pin_cfg->type, pin_cfg->num);
492			return false;
493		}
494	}
495
496	return true;
497}
498
499static int tegra_kbc_parse_dt(struct tegra_kbc *kbc)
500{
501	struct device_node *np = kbc->dev->of_node;
502	u32 prop;
503	int i;
504	u32 num_rows = 0;
505	u32 num_cols = 0;
506	u32 cols_cfg[KBC_MAX_GPIO];
507	u32 rows_cfg[KBC_MAX_GPIO];
508	int proplen;
509	int ret;
510
511	if (!of_property_read_u32(np, "nvidia,debounce-delay-ms", &prop))
512		kbc->debounce_cnt = prop;
513
514	if (!of_property_read_u32(np, "nvidia,repeat-delay-ms", &prop))
515		kbc->repeat_cnt = prop;
516
517	if (of_find_property(np, "nvidia,needs-ghost-filter", NULL))
518		kbc->use_ghost_filter = true;
519
520	if (of_property_read_bool(np, "wakeup-source") ||
521	    of_property_read_bool(np, "nvidia,wakeup-source")) /* legacy */
522		kbc->wakeup = true;
523
524	if (!of_get_property(np, "nvidia,kbc-row-pins", &proplen)) {
525		dev_err(kbc->dev, "property nvidia,kbc-row-pins not found\n");
526		return -ENOENT;
527	}
528	num_rows = proplen / sizeof(u32);
529
530	if (!of_get_property(np, "nvidia,kbc-col-pins", &proplen)) {
531		dev_err(kbc->dev, "property nvidia,kbc-col-pins not found\n");
532		return -ENOENT;
533	}
534	num_cols = proplen / sizeof(u32);
535
536	if (num_rows > kbc->hw_support->max_rows) {
537		dev_err(kbc->dev,
538			"Number of rows is more than supported by hardware\n");
539		return -EINVAL;
540	}
541
542	if (num_cols > kbc->hw_support->max_columns) {
543		dev_err(kbc->dev,
544			"Number of cols is more than supported by hardware\n");
545		return -EINVAL;
546	}
547
548	if (!of_get_property(np, "linux,keymap", &proplen)) {
549		dev_err(kbc->dev, "property linux,keymap not found\n");
550		return -ENOENT;
551	}
552
553	if (!num_rows || !num_cols || ((num_rows + num_cols) > KBC_MAX_GPIO)) {
554		dev_err(kbc->dev,
555			"keypad rows/columns not porperly specified\n");
556		return -EINVAL;
557	}
558
559	/* Set all pins as non-configured */
560	for (i = 0; i < kbc->num_rows_and_columns; i++)
561		kbc->pin_cfg[i].type = PIN_CFG_IGNORE;
562
563	ret = of_property_read_u32_array(np, "nvidia,kbc-row-pins",
564				rows_cfg, num_rows);
565	if (ret < 0) {
566		dev_err(kbc->dev, "Rows configurations are not proper\n");
567		return -EINVAL;
568	}
569
570	ret = of_property_read_u32_array(np, "nvidia,kbc-col-pins",
571				cols_cfg, num_cols);
572	if (ret < 0) {
573		dev_err(kbc->dev, "Cols configurations are not proper\n");
574		return -EINVAL;
575	}
576
577	for (i = 0; i < num_rows; i++) {
578		kbc->pin_cfg[rows_cfg[i]].type = PIN_CFG_ROW;
579		kbc->pin_cfg[rows_cfg[i]].num = i;
580	}
581
582	for (i = 0; i < num_cols; i++) {
583		kbc->pin_cfg[cols_cfg[i]].type = PIN_CFG_COL;
584		kbc->pin_cfg[cols_cfg[i]].num = i;
585	}
586
587	return 0;
588}
589
590static const struct tegra_kbc_hw_support tegra20_kbc_hw_support = {
591	.max_rows	= 16,
592	.max_columns	= 8,
593};
594
595static const struct tegra_kbc_hw_support tegra11_kbc_hw_support = {
596	.max_rows	= 11,
597	.max_columns	= 8,
598};
599
600static const struct of_device_id tegra_kbc_of_match[] = {
601	{ .compatible = "nvidia,tegra114-kbc", .data = &tegra11_kbc_hw_support},
602	{ .compatible = "nvidia,tegra30-kbc", .data = &tegra20_kbc_hw_support},
603	{ .compatible = "nvidia,tegra20-kbc", .data = &tegra20_kbc_hw_support},
604	{ },
605};
606MODULE_DEVICE_TABLE(of, tegra_kbc_of_match);
607
608static int tegra_kbc_probe(struct platform_device *pdev)
609{
610	struct tegra_kbc *kbc;
611	struct resource *res;
612	int err;
613	int num_rows = 0;
614	unsigned int debounce_cnt;
615	unsigned int scan_time_rows;
616	unsigned int keymap_rows;
617	const struct of_device_id *match;
618
619	match = of_match_device(tegra_kbc_of_match, &pdev->dev);
620
621	kbc = devm_kzalloc(&pdev->dev, sizeof(*kbc), GFP_KERNEL);
622	if (!kbc) {
623		dev_err(&pdev->dev, "failed to alloc memory for kbc\n");
624		return -ENOMEM;
625	}
626
627	kbc->dev = &pdev->dev;
628	kbc->hw_support = match->data;
629	kbc->max_keys = kbc->hw_support->max_rows *
630				kbc->hw_support->max_columns;
631	kbc->num_rows_and_columns = kbc->hw_support->max_rows +
632					kbc->hw_support->max_columns;
633	keymap_rows = kbc->max_keys;
634	spin_lock_init(&kbc->lock);
635
636	err = tegra_kbc_parse_dt(kbc);
637	if (err)
638		return err;
639
640	if (!tegra_kbc_check_pin_cfg(kbc, &num_rows))
641		return -EINVAL;
642
643	kbc->irq = platform_get_irq(pdev, 0);
644	if (kbc->irq < 0) {
645		dev_err(&pdev->dev, "failed to get keyboard IRQ\n");
646		return -ENXIO;
647	}
648
649	kbc->idev = devm_input_allocate_device(&pdev->dev);
650	if (!kbc->idev) {
651		dev_err(&pdev->dev, "failed to allocate input device\n");
652		return -ENOMEM;
653	}
654
655	setup_timer(&kbc->timer, tegra_kbc_keypress_timer, (unsigned long)kbc);
656
657	res = platform_get_resource(pdev, IORESOURCE_MEM, 0);
658	kbc->mmio = devm_ioremap_resource(&pdev->dev, res);
659	if (IS_ERR(kbc->mmio))
660		return PTR_ERR(kbc->mmio);
661
662	kbc->clk = devm_clk_get(&pdev->dev, NULL);
663	if (IS_ERR(kbc->clk)) {
664		dev_err(&pdev->dev, "failed to get keyboard clock\n");
665		return PTR_ERR(kbc->clk);
666	}
667
668	kbc->rst = devm_reset_control_get(&pdev->dev, "kbc");
669	if (IS_ERR(kbc->rst)) {
670		dev_err(&pdev->dev, "failed to get keyboard reset\n");
671		return PTR_ERR(kbc->rst);
672	}
673
674	/*
675	 * The time delay between two consecutive reads of the FIFO is
676	 * the sum of the repeat time and the time taken for scanning
677	 * the rows. There is an additional delay before the row scanning
678	 * starts. The repoll delay is computed in milliseconds.
679	 */
680	debounce_cnt = min(kbc->debounce_cnt, KBC_MAX_DEBOUNCE_CNT);
681	scan_time_rows = (KBC_ROW_SCAN_TIME + debounce_cnt) * num_rows;
682	kbc->repoll_dly = KBC_ROW_SCAN_DLY + scan_time_rows + kbc->repeat_cnt;
683	kbc->repoll_dly = DIV_ROUND_UP(kbc->repoll_dly, KBC_CYCLE_MS);
684
685	kbc->idev->name = pdev->name;
686	kbc->idev->id.bustype = BUS_HOST;
687	kbc->idev->dev.parent = &pdev->dev;
688	kbc->idev->open = tegra_kbc_open;
689	kbc->idev->close = tegra_kbc_close;
690
691	if (kbc->keymap_data && kbc->use_fn_map)
692		keymap_rows *= 2;
693
694	err = matrix_keypad_build_keymap(kbc->keymap_data, NULL,
695					 keymap_rows,
696					 kbc->hw_support->max_columns,
697					 kbc->keycode, kbc->idev);
698	if (err) {
699		dev_err(&pdev->dev, "failed to setup keymap\n");
700		return err;
701	}
702
703	__set_bit(EV_REP, kbc->idev->evbit);
704	input_set_capability(kbc->idev, EV_MSC, MSC_SCAN);
705
706	input_set_drvdata(kbc->idev, kbc);
707
708	err = devm_request_irq(&pdev->dev, kbc->irq, tegra_kbc_isr,
709			       IRQF_TRIGGER_HIGH, pdev->name, kbc);
 
710	if (err) {
711		dev_err(&pdev->dev, "failed to request keyboard IRQ\n");
712		return err;
713	}
714
715	disable_irq(kbc->irq);
716
717	err = input_register_device(kbc->idev);
718	if (err) {
719		dev_err(&pdev->dev, "failed to register input device\n");
720		return err;
721	}
722
723	platform_set_drvdata(pdev, kbc);
724	device_init_wakeup(&pdev->dev, kbc->wakeup);
725
726	return 0;
727}
728
729#ifdef CONFIG_PM_SLEEP
730static void tegra_kbc_set_keypress_interrupt(struct tegra_kbc *kbc, bool enable)
731{
732	u32 val;
733
734	val = readl(kbc->mmio + KBC_CONTROL_0);
735	if (enable)
736		val |= KBC_CONTROL_KEYPRESS_INT_EN;
737	else
738		val &= ~KBC_CONTROL_KEYPRESS_INT_EN;
739	writel(val, kbc->mmio + KBC_CONTROL_0);
740}
741
742static int tegra_kbc_suspend(struct device *dev)
743{
744	struct platform_device *pdev = to_platform_device(dev);
745	struct tegra_kbc *kbc = platform_get_drvdata(pdev);
746
747	mutex_lock(&kbc->idev->mutex);
748	if (device_may_wakeup(&pdev->dev)) {
749		disable_irq(kbc->irq);
750		del_timer_sync(&kbc->timer);
751		tegra_kbc_set_fifo_interrupt(kbc, false);
752
753		/* Forcefully clear the interrupt status */
754		writel(0x7, kbc->mmio + KBC_INT_0);
755		/*
756		 * Store the previous resident time of continuous polling mode.
757		 * Force the keyboard into interrupt mode.
758		 */
759		kbc->cp_to_wkup_dly = readl(kbc->mmio + KBC_TO_CNT_0);
760		writel(0, kbc->mmio + KBC_TO_CNT_0);
761
762		tegra_kbc_setup_wakekeys(kbc, true);
763		msleep(30);
764
765		kbc->keypress_caused_wake = false;
766		/* Enable keypress interrupt before going into suspend. */
767		tegra_kbc_set_keypress_interrupt(kbc, true);
768		enable_irq(kbc->irq);
769		enable_irq_wake(kbc->irq);
770	} else {
771		if (kbc->idev->users)
772			tegra_kbc_stop(kbc);
773	}
774	mutex_unlock(&kbc->idev->mutex);
775
776	return 0;
777}
778
779static int tegra_kbc_resume(struct device *dev)
780{
781	struct platform_device *pdev = to_platform_device(dev);
782	struct tegra_kbc *kbc = platform_get_drvdata(pdev);
783	int err = 0;
784
785	mutex_lock(&kbc->idev->mutex);
786	if (device_may_wakeup(&pdev->dev)) {
787		disable_irq_wake(kbc->irq);
788		tegra_kbc_setup_wakekeys(kbc, false);
789		/* We will use fifo interrupts for key detection. */
790		tegra_kbc_set_keypress_interrupt(kbc, false);
791
792		/* Restore the resident time of continuous polling mode. */
793		writel(kbc->cp_to_wkup_dly, kbc->mmio + KBC_TO_CNT_0);
794
795		tegra_kbc_set_fifo_interrupt(kbc, true);
796
797		if (kbc->keypress_caused_wake && kbc->wakeup_key) {
798			/*
799			 * We can't report events directly from the ISR
800			 * because timekeeping is stopped when processing
801			 * wakeup request and we get a nasty warning when
802			 * we try to call do_gettimeofday() in evdev
803			 * handler.
804			 */
805			input_report_key(kbc->idev, kbc->wakeup_key, 1);
806			input_sync(kbc->idev);
807			input_report_key(kbc->idev, kbc->wakeup_key, 0);
808			input_sync(kbc->idev);
809		}
810	} else {
811		if (kbc->idev->users)
812			err = tegra_kbc_start(kbc);
813	}
814	mutex_unlock(&kbc->idev->mutex);
815
816	return err;
817}
818#endif
819
820static SIMPLE_DEV_PM_OPS(tegra_kbc_pm_ops, tegra_kbc_suspend, tegra_kbc_resume);
 
821
822static struct platform_driver tegra_kbc_driver = {
823	.probe		= tegra_kbc_probe,
824	.driver	= {
825		.name	= "tegra-kbc",
826		.pm	= &tegra_kbc_pm_ops,
827		.of_match_table = tegra_kbc_of_match,
828	},
829};
830module_platform_driver(tegra_kbc_driver);
831
832MODULE_LICENSE("GPL");
833MODULE_AUTHOR("Rakesh Iyer <riyer@nvidia.com>");
834MODULE_DESCRIPTION("Tegra matrix keyboard controller driver");
835MODULE_ALIAS("platform:tegra-kbc");
v6.9.4
  1// SPDX-License-Identifier: GPL-2.0-or-later
  2/*
  3 * Keyboard class input driver for the NVIDIA Tegra SoC internal matrix
  4 * keyboard controller
  5 *
  6 * Copyright (c) 2009-2011, NVIDIA Corporation.
 
 
 
 
 
 
 
 
 
 
 
 
 
 
  7 */
  8
  9#include <linux/kernel.h>
 10#include <linux/module.h>
 11#include <linux/input.h>
 12#include <linux/platform_device.h>
 13#include <linux/delay.h>
 14#include <linux/io.h>
 15#include <linux/interrupt.h>
 16#include <linux/of.h>
 17#include <linux/property.h>
 18#include <linux/clk.h>
 19#include <linux/slab.h>
 20#include <linux/input/matrix_keypad.h>
 21#include <linux/reset.h>
 22#include <linux/err.h>
 23
 24#define KBC_MAX_KPENT	8
 25
 26/* Maximum row/column supported by Tegra KBC yet  is 16x8 */
 27#define KBC_MAX_GPIO	24
 28/* Maximum keys supported by Tegra KBC yet is 16 x 8*/
 29#define KBC_MAX_KEY	(16 * 8)
 30
 31#define KBC_MAX_DEBOUNCE_CNT	0x3ffu
 32
 33/* KBC row scan time and delay for beginning the row scan. */
 34#define KBC_ROW_SCAN_TIME	16
 35#define KBC_ROW_SCAN_DLY	5
 36
 37/* KBC uses a 32KHz clock so a cycle = 1/32Khz */
 38#define KBC_CYCLE_MS	32
 39
 40/* KBC Registers */
 41
 42/* KBC Control Register */
 43#define KBC_CONTROL_0	0x0
 44#define KBC_FIFO_TH_CNT_SHIFT(cnt)	(cnt << 14)
 45#define KBC_DEBOUNCE_CNT_SHIFT(cnt)	(cnt << 4)
 46#define KBC_CONTROL_FIFO_CNT_INT_EN	(1 << 3)
 47#define KBC_CONTROL_KEYPRESS_INT_EN	(1 << 1)
 48#define KBC_CONTROL_KBC_EN		(1 << 0)
 49
 50/* KBC Interrupt Register */
 51#define KBC_INT_0	0x4
 52#define KBC_INT_FIFO_CNT_INT_STATUS	(1 << 2)
 53#define KBC_INT_KEYPRESS_INT_STATUS	(1 << 0)
 54
 55#define KBC_ROW_CFG0_0	0x8
 56#define KBC_COL_CFG0_0	0x18
 57#define KBC_TO_CNT_0	0x24
 58#define KBC_INIT_DLY_0	0x28
 59#define KBC_RPT_DLY_0	0x2c
 60#define KBC_KP_ENT0_0	0x30
 61#define KBC_KP_ENT1_0	0x34
 62#define KBC_ROW0_MASK_0	0x38
 63
 64#define KBC_ROW_SHIFT	3
 65
 66enum tegra_pin_type {
 67	PIN_CFG_IGNORE,
 68	PIN_CFG_COL,
 69	PIN_CFG_ROW,
 70};
 71
 72/* Tegra KBC hw support */
 73struct tegra_kbc_hw_support {
 74	int max_rows;
 75	int max_columns;
 76};
 77
 78struct tegra_kbc_pin_cfg {
 79	enum tegra_pin_type type;
 80	unsigned char num;
 81};
 82
 83struct tegra_kbc {
 84	struct device *dev;
 85	unsigned int debounce_cnt;
 86	unsigned int repeat_cnt;
 87	struct tegra_kbc_pin_cfg pin_cfg[KBC_MAX_GPIO];
 88	const struct matrix_keymap_data *keymap_data;
 89	bool wakeup;
 90	void __iomem *mmio;
 91	struct input_dev *idev;
 92	int irq;
 93	spinlock_t lock;
 94	unsigned int repoll_dly;
 95	unsigned long cp_dly_jiffies;
 96	unsigned int cp_to_wkup_dly;
 97	bool use_fn_map;
 98	bool use_ghost_filter;
 99	bool keypress_caused_wake;
100	unsigned short keycode[KBC_MAX_KEY * 2];
101	unsigned short current_keys[KBC_MAX_KPENT];
102	unsigned int num_pressed_keys;
103	u32 wakeup_key;
104	struct timer_list timer;
105	struct clk *clk;
106	struct reset_control *rst;
107	const struct tegra_kbc_hw_support *hw_support;
108	int max_keys;
109	int num_rows_and_columns;
110};
111
112static void tegra_kbc_report_released_keys(struct input_dev *input,
113					   unsigned short old_keycodes[],
114					   unsigned int old_num_keys,
115					   unsigned short new_keycodes[],
116					   unsigned int new_num_keys)
117{
118	unsigned int i, j;
119
120	for (i = 0; i < old_num_keys; i++) {
121		for (j = 0; j < new_num_keys; j++)
122			if (old_keycodes[i] == new_keycodes[j])
123				break;
124
125		if (j == new_num_keys)
126			input_report_key(input, old_keycodes[i], 0);
127	}
128}
129
130static void tegra_kbc_report_pressed_keys(struct input_dev *input,
131					  unsigned char scancodes[],
132					  unsigned short keycodes[],
133					  unsigned int num_pressed_keys)
134{
135	unsigned int i;
136
137	for (i = 0; i < num_pressed_keys; i++) {
138		input_event(input, EV_MSC, MSC_SCAN, scancodes[i]);
139		input_report_key(input, keycodes[i], 1);
140	}
141}
142
143static void tegra_kbc_report_keys(struct tegra_kbc *kbc)
144{
145	unsigned char scancodes[KBC_MAX_KPENT];
146	unsigned short keycodes[KBC_MAX_KPENT];
147	u32 val = 0;
148	unsigned int i;
149	unsigned int num_down = 0;
150	bool fn_keypress = false;
151	bool key_in_same_row = false;
152	bool key_in_same_col = false;
153
154	for (i = 0; i < KBC_MAX_KPENT; i++) {
155		if ((i % 4) == 0)
156			val = readl(kbc->mmio + KBC_KP_ENT0_0 + i);
157
158		if (val & 0x80) {
159			unsigned int col = val & 0x07;
160			unsigned int row = (val >> 3) & 0x0f;
161			unsigned char scancode =
162				MATRIX_SCAN_CODE(row, col, KBC_ROW_SHIFT);
163
164			scancodes[num_down] = scancode;
165			keycodes[num_down] = kbc->keycode[scancode];
166			/* If driver uses Fn map, do not report the Fn key. */
167			if ((keycodes[num_down] == KEY_FN) && kbc->use_fn_map)
168				fn_keypress = true;
169			else
170				num_down++;
171		}
172
173		val >>= 8;
174	}
175
176	/*
177	 * Matrix keyboard designs are prone to keyboard ghosting.
178	 * Ghosting occurs if there are 3 keys such that -
179	 * any 2 of the 3 keys share a row, and any 2 of them share a column.
180	 * If so ignore the key presses for this iteration.
181	 */
182	if (kbc->use_ghost_filter && num_down >= 3) {
183		for (i = 0; i < num_down; i++) {
184			unsigned int j;
185			u8 curr_col = scancodes[i] & 0x07;
186			u8 curr_row = scancodes[i] >> KBC_ROW_SHIFT;
187
188			/*
189			 * Find 2 keys such that one key is in the same row
190			 * and the other is in the same column as the i-th key.
191			 */
192			for (j = i + 1; j < num_down; j++) {
193				u8 col = scancodes[j] & 0x07;
194				u8 row = scancodes[j] >> KBC_ROW_SHIFT;
195
196				if (col == curr_col)
197					key_in_same_col = true;
198				if (row == curr_row)
199					key_in_same_row = true;
200			}
201		}
202	}
203
204	/*
205	 * If the platform uses Fn keymaps, translate keys on a Fn keypress.
206	 * Function keycodes are max_keys apart from the plain keycodes.
207	 */
208	if (fn_keypress) {
209		for (i = 0; i < num_down; i++) {
210			scancodes[i] += kbc->max_keys;
211			keycodes[i] = kbc->keycode[scancodes[i]];
212		}
213	}
214
215	/* Ignore the key presses for this iteration? */
216	if (key_in_same_col && key_in_same_row)
217		return;
218
219	tegra_kbc_report_released_keys(kbc->idev,
220				       kbc->current_keys, kbc->num_pressed_keys,
221				       keycodes, num_down);
222	tegra_kbc_report_pressed_keys(kbc->idev, scancodes, keycodes, num_down);
223	input_sync(kbc->idev);
224
225	memcpy(kbc->current_keys, keycodes, sizeof(kbc->current_keys));
226	kbc->num_pressed_keys = num_down;
227}
228
229static void tegra_kbc_set_fifo_interrupt(struct tegra_kbc *kbc, bool enable)
230{
231	u32 val;
232
233	val = readl(kbc->mmio + KBC_CONTROL_0);
234	if (enable)
235		val |= KBC_CONTROL_FIFO_CNT_INT_EN;
236	else
237		val &= ~KBC_CONTROL_FIFO_CNT_INT_EN;
238	writel(val, kbc->mmio + KBC_CONTROL_0);
239}
240
241static void tegra_kbc_keypress_timer(struct timer_list *t)
242{
243	struct tegra_kbc *kbc = from_timer(kbc, t, timer);
244	unsigned long flags;
245	u32 val;
246	unsigned int i;
247
248	spin_lock_irqsave(&kbc->lock, flags);
249
250	val = (readl(kbc->mmio + KBC_INT_0) >> 4) & 0xf;
251	if (val) {
252		unsigned long dly;
253
254		tegra_kbc_report_keys(kbc);
255
256		/*
257		 * If more than one keys are pressed we need not wait
258		 * for the repoll delay.
259		 */
260		dly = (val == 1) ? kbc->repoll_dly : 1;
261		mod_timer(&kbc->timer, jiffies + msecs_to_jiffies(dly));
262	} else {
263		/* Release any pressed keys and exit the polling loop */
264		for (i = 0; i < kbc->num_pressed_keys; i++)
265			input_report_key(kbc->idev, kbc->current_keys[i], 0);
266		input_sync(kbc->idev);
267
268		kbc->num_pressed_keys = 0;
269
270		/* All keys are released so enable the keypress interrupt */
271		tegra_kbc_set_fifo_interrupt(kbc, true);
272	}
273
274	spin_unlock_irqrestore(&kbc->lock, flags);
275}
276
277static irqreturn_t tegra_kbc_isr(int irq, void *args)
278{
279	struct tegra_kbc *kbc = args;
280	unsigned long flags;
281	u32 val;
282
283	spin_lock_irqsave(&kbc->lock, flags);
284
285	/*
286	 * Quickly bail out & reenable interrupts if the fifo threshold
287	 * count interrupt wasn't the interrupt source
288	 */
289	val = readl(kbc->mmio + KBC_INT_0);
290	writel(val, kbc->mmio + KBC_INT_0);
291
292	if (val & KBC_INT_FIFO_CNT_INT_STATUS) {
293		/*
294		 * Until all keys are released, defer further processing to
295		 * the polling loop in tegra_kbc_keypress_timer.
296		 */
297		tegra_kbc_set_fifo_interrupt(kbc, false);
298		mod_timer(&kbc->timer, jiffies + kbc->cp_dly_jiffies);
299	} else if (val & KBC_INT_KEYPRESS_INT_STATUS) {
300		/* We can be here only through system resume path */
301		kbc->keypress_caused_wake = true;
302	}
303
304	spin_unlock_irqrestore(&kbc->lock, flags);
305
306	return IRQ_HANDLED;
307}
308
309static void tegra_kbc_setup_wakekeys(struct tegra_kbc *kbc, bool filter)
310{
311	int i;
312	unsigned int rst_val;
313
314	/* Either mask all keys or none. */
315	rst_val = (filter && !kbc->wakeup) ? ~0 : 0;
316
317	for (i = 0; i < kbc->hw_support->max_rows; i++)
318		writel(rst_val, kbc->mmio + KBC_ROW0_MASK_0 + i * 4);
319}
320
321static void tegra_kbc_config_pins(struct tegra_kbc *kbc)
322{
323	int i;
324
325	for (i = 0; i < KBC_MAX_GPIO; i++) {
326		u32 r_shft = 5 * (i % 6);
327		u32 c_shft = 4 * (i % 8);
328		u32 r_mask = 0x1f << r_shft;
329		u32 c_mask = 0x0f << c_shft;
330		u32 r_offs = (i / 6) * 4 + KBC_ROW_CFG0_0;
331		u32 c_offs = (i / 8) * 4 + KBC_COL_CFG0_0;
332		u32 row_cfg = readl(kbc->mmio + r_offs);
333		u32 col_cfg = readl(kbc->mmio + c_offs);
334
335		row_cfg &= ~r_mask;
336		col_cfg &= ~c_mask;
337
338		switch (kbc->pin_cfg[i].type) {
339		case PIN_CFG_ROW:
340			row_cfg |= ((kbc->pin_cfg[i].num << 1) | 1) << r_shft;
341			break;
342
343		case PIN_CFG_COL:
344			col_cfg |= ((kbc->pin_cfg[i].num << 1) | 1) << c_shft;
345			break;
346
347		case PIN_CFG_IGNORE:
348			break;
349		}
350
351		writel(row_cfg, kbc->mmio + r_offs);
352		writel(col_cfg, kbc->mmio + c_offs);
353	}
354}
355
356static int tegra_kbc_start(struct tegra_kbc *kbc)
357{
358	unsigned int debounce_cnt;
359	u32 val = 0;
360	int ret;
361
362	ret = clk_prepare_enable(kbc->clk);
363	if (ret)
364		return ret;
365
366	/* Reset the KBC controller to clear all previous status.*/
367	reset_control_assert(kbc->rst);
368	udelay(100);
369	reset_control_deassert(kbc->rst);
370	udelay(100);
371
372	tegra_kbc_config_pins(kbc);
373	tegra_kbc_setup_wakekeys(kbc, false);
374
375	writel(kbc->repeat_cnt, kbc->mmio + KBC_RPT_DLY_0);
376
377	/* Keyboard debounce count is maximum of 12 bits. */
378	debounce_cnt = min(kbc->debounce_cnt, KBC_MAX_DEBOUNCE_CNT);
379	val = KBC_DEBOUNCE_CNT_SHIFT(debounce_cnt);
380	val |= KBC_FIFO_TH_CNT_SHIFT(1); /* set fifo interrupt threshold to 1 */
381	val |= KBC_CONTROL_FIFO_CNT_INT_EN;  /* interrupt on FIFO threshold */
382	val |= KBC_CONTROL_KBC_EN;     /* enable */
383	writel(val, kbc->mmio + KBC_CONTROL_0);
384
385	/*
386	 * Compute the delay(ns) from interrupt mode to continuous polling
387	 * mode so the timer routine is scheduled appropriately.
388	 */
389	val = readl(kbc->mmio + KBC_INIT_DLY_0);
390	kbc->cp_dly_jiffies = usecs_to_jiffies((val & 0xfffff) * 32);
391
392	kbc->num_pressed_keys = 0;
393
394	/*
395	 * Atomically clear out any remaining entries in the key FIFO
396	 * and enable keyboard interrupts.
397	 */
398	while (1) {
399		val = readl(kbc->mmio + KBC_INT_0);
400		val >>= 4;
401		if (!val)
402			break;
403
404		val = readl(kbc->mmio + KBC_KP_ENT0_0);
405		val = readl(kbc->mmio + KBC_KP_ENT1_0);
406	}
407	writel(0x7, kbc->mmio + KBC_INT_0);
408
409	enable_irq(kbc->irq);
410
411	return 0;
412}
413
414static void tegra_kbc_stop(struct tegra_kbc *kbc)
415{
416	unsigned long flags;
417	u32 val;
418
419	spin_lock_irqsave(&kbc->lock, flags);
420	val = readl(kbc->mmio + KBC_CONTROL_0);
421	val &= ~1;
422	writel(val, kbc->mmio + KBC_CONTROL_0);
423	spin_unlock_irqrestore(&kbc->lock, flags);
424
425	disable_irq(kbc->irq);
426	del_timer_sync(&kbc->timer);
427
428	clk_disable_unprepare(kbc->clk);
429}
430
431static int tegra_kbc_open(struct input_dev *dev)
432{
433	struct tegra_kbc *kbc = input_get_drvdata(dev);
434
435	return tegra_kbc_start(kbc);
436}
437
438static void tegra_kbc_close(struct input_dev *dev)
439{
440	struct tegra_kbc *kbc = input_get_drvdata(dev);
441
442	return tegra_kbc_stop(kbc);
443}
444
445static bool tegra_kbc_check_pin_cfg(const struct tegra_kbc *kbc,
446					unsigned int *num_rows)
447{
448	int i;
449
450	*num_rows = 0;
451
452	for (i = 0; i < KBC_MAX_GPIO; i++) {
453		const struct tegra_kbc_pin_cfg *pin_cfg = &kbc->pin_cfg[i];
454
455		switch (pin_cfg->type) {
456		case PIN_CFG_ROW:
457			if (pin_cfg->num >= kbc->hw_support->max_rows) {
458				dev_err(kbc->dev,
459					"pin_cfg[%d]: invalid row number %d\n",
460					i, pin_cfg->num);
461				return false;
462			}
463			(*num_rows)++;
464			break;
465
466		case PIN_CFG_COL:
467			if (pin_cfg->num >= kbc->hw_support->max_columns) {
468				dev_err(kbc->dev,
469					"pin_cfg[%d]: invalid column number %d\n",
470					i, pin_cfg->num);
471				return false;
472			}
473			break;
474
475		case PIN_CFG_IGNORE:
476			break;
477
478		default:
479			dev_err(kbc->dev,
480				"pin_cfg[%d]: invalid entry type %d\n",
481				pin_cfg->type, pin_cfg->num);
482			return false;
483		}
484	}
485
486	return true;
487}
488
489static int tegra_kbc_parse_dt(struct tegra_kbc *kbc)
490{
491	struct device_node *np = kbc->dev->of_node;
492	u32 prop;
493	int i;
494	u32 num_rows = 0;
495	u32 num_cols = 0;
496	u32 cols_cfg[KBC_MAX_GPIO];
497	u32 rows_cfg[KBC_MAX_GPIO];
498	int proplen;
499	int ret;
500
501	if (!of_property_read_u32(np, "nvidia,debounce-delay-ms", &prop))
502		kbc->debounce_cnt = prop;
503
504	if (!of_property_read_u32(np, "nvidia,repeat-delay-ms", &prop))
505		kbc->repeat_cnt = prop;
506
507	kbc->use_ghost_filter = of_property_present(np, "nvidia,needs-ghost-filter");
 
508
509	if (of_property_read_bool(np, "wakeup-source") ||
510	    of_property_read_bool(np, "nvidia,wakeup-source")) /* legacy */
511		kbc->wakeup = true;
512
513	if (!of_get_property(np, "nvidia,kbc-row-pins", &proplen)) {
514		dev_err(kbc->dev, "property nvidia,kbc-row-pins not found\n");
515		return -ENOENT;
516	}
517	num_rows = proplen / sizeof(u32);
518
519	if (!of_get_property(np, "nvidia,kbc-col-pins", &proplen)) {
520		dev_err(kbc->dev, "property nvidia,kbc-col-pins not found\n");
521		return -ENOENT;
522	}
523	num_cols = proplen / sizeof(u32);
524
525	if (num_rows > kbc->hw_support->max_rows) {
526		dev_err(kbc->dev,
527			"Number of rows is more than supported by hardware\n");
528		return -EINVAL;
529	}
530
531	if (num_cols > kbc->hw_support->max_columns) {
532		dev_err(kbc->dev,
533			"Number of cols is more than supported by hardware\n");
534		return -EINVAL;
535	}
536
537	if (!of_get_property(np, "linux,keymap", &proplen)) {
538		dev_err(kbc->dev, "property linux,keymap not found\n");
539		return -ENOENT;
540	}
541
542	if (!num_rows || !num_cols || ((num_rows + num_cols) > KBC_MAX_GPIO)) {
543		dev_err(kbc->dev,
544			"keypad rows/columns not properly specified\n");
545		return -EINVAL;
546	}
547
548	/* Set all pins as non-configured */
549	for (i = 0; i < kbc->num_rows_and_columns; i++)
550		kbc->pin_cfg[i].type = PIN_CFG_IGNORE;
551
552	ret = of_property_read_u32_array(np, "nvidia,kbc-row-pins",
553				rows_cfg, num_rows);
554	if (ret < 0) {
555		dev_err(kbc->dev, "Rows configurations are not proper\n");
556		return -EINVAL;
557	}
558
559	ret = of_property_read_u32_array(np, "nvidia,kbc-col-pins",
560				cols_cfg, num_cols);
561	if (ret < 0) {
562		dev_err(kbc->dev, "Cols configurations are not proper\n");
563		return -EINVAL;
564	}
565
566	for (i = 0; i < num_rows; i++) {
567		kbc->pin_cfg[rows_cfg[i]].type = PIN_CFG_ROW;
568		kbc->pin_cfg[rows_cfg[i]].num = i;
569	}
570
571	for (i = 0; i < num_cols; i++) {
572		kbc->pin_cfg[cols_cfg[i]].type = PIN_CFG_COL;
573		kbc->pin_cfg[cols_cfg[i]].num = i;
574	}
575
576	return 0;
577}
578
579static const struct tegra_kbc_hw_support tegra20_kbc_hw_support = {
580	.max_rows	= 16,
581	.max_columns	= 8,
582};
583
584static const struct tegra_kbc_hw_support tegra11_kbc_hw_support = {
585	.max_rows	= 11,
586	.max_columns	= 8,
587};
588
589static const struct of_device_id tegra_kbc_of_match[] = {
590	{ .compatible = "nvidia,tegra114-kbc", .data = &tegra11_kbc_hw_support},
591	{ .compatible = "nvidia,tegra30-kbc", .data = &tegra20_kbc_hw_support},
592	{ .compatible = "nvidia,tegra20-kbc", .data = &tegra20_kbc_hw_support},
593	{ },
594};
595MODULE_DEVICE_TABLE(of, tegra_kbc_of_match);
596
597static int tegra_kbc_probe(struct platform_device *pdev)
598{
599	struct tegra_kbc *kbc;
 
600	int err;
601	int num_rows = 0;
602	unsigned int debounce_cnt;
603	unsigned int scan_time_rows;
604	unsigned int keymap_rows;
 
 
 
605
606	kbc = devm_kzalloc(&pdev->dev, sizeof(*kbc), GFP_KERNEL);
607	if (!kbc) {
608		dev_err(&pdev->dev, "failed to alloc memory for kbc\n");
609		return -ENOMEM;
610	}
611
612	kbc->dev = &pdev->dev;
613	kbc->hw_support = device_get_match_data(&pdev->dev);
614	kbc->max_keys = kbc->hw_support->max_rows *
615				kbc->hw_support->max_columns;
616	kbc->num_rows_and_columns = kbc->hw_support->max_rows +
617					kbc->hw_support->max_columns;
618	keymap_rows = kbc->max_keys;
619	spin_lock_init(&kbc->lock);
620
621	err = tegra_kbc_parse_dt(kbc);
622	if (err)
623		return err;
624
625	if (!tegra_kbc_check_pin_cfg(kbc, &num_rows))
626		return -EINVAL;
627
628	kbc->irq = platform_get_irq(pdev, 0);
629	if (kbc->irq < 0)
 
630		return -ENXIO;
 
631
632	kbc->idev = devm_input_allocate_device(&pdev->dev);
633	if (!kbc->idev) {
634		dev_err(&pdev->dev, "failed to allocate input device\n");
635		return -ENOMEM;
636	}
637
638	timer_setup(&kbc->timer, tegra_kbc_keypress_timer, 0);
639
640	kbc->mmio = devm_platform_ioremap_resource(pdev, 0);
 
641	if (IS_ERR(kbc->mmio))
642		return PTR_ERR(kbc->mmio);
643
644	kbc->clk = devm_clk_get(&pdev->dev, NULL);
645	if (IS_ERR(kbc->clk)) {
646		dev_err(&pdev->dev, "failed to get keyboard clock\n");
647		return PTR_ERR(kbc->clk);
648	}
649
650	kbc->rst = devm_reset_control_get(&pdev->dev, "kbc");
651	if (IS_ERR(kbc->rst)) {
652		dev_err(&pdev->dev, "failed to get keyboard reset\n");
653		return PTR_ERR(kbc->rst);
654	}
655
656	/*
657	 * The time delay between two consecutive reads of the FIFO is
658	 * the sum of the repeat time and the time taken for scanning
659	 * the rows. There is an additional delay before the row scanning
660	 * starts. The repoll delay is computed in milliseconds.
661	 */
662	debounce_cnt = min(kbc->debounce_cnt, KBC_MAX_DEBOUNCE_CNT);
663	scan_time_rows = (KBC_ROW_SCAN_TIME + debounce_cnt) * num_rows;
664	kbc->repoll_dly = KBC_ROW_SCAN_DLY + scan_time_rows + kbc->repeat_cnt;
665	kbc->repoll_dly = DIV_ROUND_UP(kbc->repoll_dly, KBC_CYCLE_MS);
666
667	kbc->idev->name = pdev->name;
668	kbc->idev->id.bustype = BUS_HOST;
669	kbc->idev->dev.parent = &pdev->dev;
670	kbc->idev->open = tegra_kbc_open;
671	kbc->idev->close = tegra_kbc_close;
672
673	if (kbc->keymap_data && kbc->use_fn_map)
674		keymap_rows *= 2;
675
676	err = matrix_keypad_build_keymap(kbc->keymap_data, NULL,
677					 keymap_rows,
678					 kbc->hw_support->max_columns,
679					 kbc->keycode, kbc->idev);
680	if (err) {
681		dev_err(&pdev->dev, "failed to setup keymap\n");
682		return err;
683	}
684
685	__set_bit(EV_REP, kbc->idev->evbit);
686	input_set_capability(kbc->idev, EV_MSC, MSC_SCAN);
687
688	input_set_drvdata(kbc->idev, kbc);
689
690	err = devm_request_irq(&pdev->dev, kbc->irq, tegra_kbc_isr,
691			       IRQF_TRIGGER_HIGH | IRQF_NO_AUTOEN,
692			       pdev->name, kbc);
693	if (err) {
694		dev_err(&pdev->dev, "failed to request keyboard IRQ\n");
695		return err;
696	}
697
 
 
698	err = input_register_device(kbc->idev);
699	if (err) {
700		dev_err(&pdev->dev, "failed to register input device\n");
701		return err;
702	}
703
704	platform_set_drvdata(pdev, kbc);
705	device_init_wakeup(&pdev->dev, kbc->wakeup);
706
707	return 0;
708}
709
 
710static void tegra_kbc_set_keypress_interrupt(struct tegra_kbc *kbc, bool enable)
711{
712	u32 val;
713
714	val = readl(kbc->mmio + KBC_CONTROL_0);
715	if (enable)
716		val |= KBC_CONTROL_KEYPRESS_INT_EN;
717	else
718		val &= ~KBC_CONTROL_KEYPRESS_INT_EN;
719	writel(val, kbc->mmio + KBC_CONTROL_0);
720}
721
722static int tegra_kbc_suspend(struct device *dev)
723{
724	struct platform_device *pdev = to_platform_device(dev);
725	struct tegra_kbc *kbc = platform_get_drvdata(pdev);
726
727	mutex_lock(&kbc->idev->mutex);
728	if (device_may_wakeup(&pdev->dev)) {
729		disable_irq(kbc->irq);
730		del_timer_sync(&kbc->timer);
731		tegra_kbc_set_fifo_interrupt(kbc, false);
732
733		/* Forcefully clear the interrupt status */
734		writel(0x7, kbc->mmio + KBC_INT_0);
735		/*
736		 * Store the previous resident time of continuous polling mode.
737		 * Force the keyboard into interrupt mode.
738		 */
739		kbc->cp_to_wkup_dly = readl(kbc->mmio + KBC_TO_CNT_0);
740		writel(0, kbc->mmio + KBC_TO_CNT_0);
741
742		tegra_kbc_setup_wakekeys(kbc, true);
743		msleep(30);
744
745		kbc->keypress_caused_wake = false;
746		/* Enable keypress interrupt before going into suspend. */
747		tegra_kbc_set_keypress_interrupt(kbc, true);
748		enable_irq(kbc->irq);
749		enable_irq_wake(kbc->irq);
750	} else {
751		if (input_device_enabled(kbc->idev))
752			tegra_kbc_stop(kbc);
753	}
754	mutex_unlock(&kbc->idev->mutex);
755
756	return 0;
757}
758
759static int tegra_kbc_resume(struct device *dev)
760{
761	struct platform_device *pdev = to_platform_device(dev);
762	struct tegra_kbc *kbc = platform_get_drvdata(pdev);
763	int err = 0;
764
765	mutex_lock(&kbc->idev->mutex);
766	if (device_may_wakeup(&pdev->dev)) {
767		disable_irq_wake(kbc->irq);
768		tegra_kbc_setup_wakekeys(kbc, false);
769		/* We will use fifo interrupts for key detection. */
770		tegra_kbc_set_keypress_interrupt(kbc, false);
771
772		/* Restore the resident time of continuous polling mode. */
773		writel(kbc->cp_to_wkup_dly, kbc->mmio + KBC_TO_CNT_0);
774
775		tegra_kbc_set_fifo_interrupt(kbc, true);
776
777		if (kbc->keypress_caused_wake && kbc->wakeup_key) {
778			/*
779			 * We can't report events directly from the ISR
780			 * because timekeeping is stopped when processing
781			 * wakeup request and we get a nasty warning when
782			 * we try to call do_gettimeofday() in evdev
783			 * handler.
784			 */
785			input_report_key(kbc->idev, kbc->wakeup_key, 1);
786			input_sync(kbc->idev);
787			input_report_key(kbc->idev, kbc->wakeup_key, 0);
788			input_sync(kbc->idev);
789		}
790	} else {
791		if (input_device_enabled(kbc->idev))
792			err = tegra_kbc_start(kbc);
793	}
794	mutex_unlock(&kbc->idev->mutex);
795
796	return err;
797}
 
798
799static DEFINE_SIMPLE_DEV_PM_OPS(tegra_kbc_pm_ops,
800				tegra_kbc_suspend, tegra_kbc_resume);
801
802static struct platform_driver tegra_kbc_driver = {
803	.probe		= tegra_kbc_probe,
804	.driver	= {
805		.name	= "tegra-kbc",
806		.pm	= pm_sleep_ptr(&tegra_kbc_pm_ops),
807		.of_match_table = tegra_kbc_of_match,
808	},
809};
810module_platform_driver(tegra_kbc_driver);
811
812MODULE_LICENSE("GPL");
813MODULE_AUTHOR("Rakesh Iyer <riyer@nvidia.com>");
814MODULE_DESCRIPTION("Tegra matrix keyboard controller driver");
815MODULE_ALIAS("platform:tegra-kbc");