Commit a48b2d4a0091904b4cf57d667adc2faf689750d3

Authored by Felipe Balbi
Committed by Dmitry Torokhov
1 parent 535650fd70

Input: introduce lm8323 keypad driver

lm8323 is the keypad driver used in n810 device.

[akpm@linux-foundation.org: coding-style fixes]
[dtor@mail.ru: various cleanups]
Signed-off-by: Felipe Balbi <felipe.balbi@nokia.com>
Reviewed-by: Trilok Soni <soni.trilok@gmail.com>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Dmitry Torokhov <dtor@mail.ru>

Showing 4 changed files with 937 additions and 1 deletions Side-by-side Diff

drivers/input/keyboard/Kconfig
... ... @@ -250,6 +250,17 @@
250 250 To compile this driver as a module, choose M here: the
251 251 module will be called jornada720_kbd.
252 252  
  253 +config KEYBOARD_LM8323
  254 + tristate "LM8323 keypad chip"
  255 + depends on I2C
  256 + depends on LEDS_CLASS
  257 + help
  258 + If you say yes here you get support for the National Semiconductor
  259 + LM8323 keypad controller.
  260 +
  261 + To compile this driver as a module, choose M here: the
  262 + module will be called lm8323.
  263 +
253 264 config KEYBOARD_OMAP
254 265 tristate "TI OMAP keypad support"
255 266 depends on (ARCH_OMAP1 || ARCH_OMAP2)
... ... @@ -332,7 +343,7 @@
332 343  
333 344 To compile this driver as a module, choose M here: the
334 345 module will be called sh_keysc.
335   -+
  346 +
336 347 config KEYBOARD_EP93XX
337 348 tristate "EP93xx Matrix Keypad support"
338 349 depends on ARCH_EP93XX
drivers/input/keyboard/Makefile
... ... @@ -18,6 +18,7 @@
18 18 obj-$(CONFIG_KEYBOARD_TOSA) += tosakbd.o
19 19 obj-$(CONFIG_KEYBOARD_HIL) += hil_kbd.o
20 20 obj-$(CONFIG_KEYBOARD_HIL_OLD) += hilkbd.o
  21 +obj-$(CONFIG_KEYBOARD_LM8323) += lm8323.o
21 22 obj-$(CONFIG_KEYBOARD_OMAP) += omap-keypad.o
22 23 obj-$(CONFIG_KEYBOARD_PXA27x) += pxa27x_keypad.o
23 24 obj-$(CONFIG_KEYBOARD_PXA930_ROTARY) += pxa930_rotary.o
drivers/input/keyboard/lm8323.c
  1 +/*
  2 + * drivers/i2c/chips/lm8323.c
  3 + *
  4 + * Copyright (C) 2007-2009 Nokia Corporation
  5 + *
  6 + * Written by Daniel Stone <daniel.stone@nokia.com>
  7 + * Timo O. Karjalainen <timo.o.karjalainen@nokia.com>
  8 + *
  9 + * Updated by Felipe Balbi <felipe.balbi@nokia.com>
  10 + *
  11 + * This program is free software; you can redistribute it and/or modify
  12 + * it under the terms of the GNU General Public License as published by
  13 + * the Free Software Foundation (version 2 of the License only).
  14 + *
  15 + * This program is distributed in the hope that it will be useful,
  16 + * but WITHOUT ANY WARRANTY; without even the implied warranty of
  17 + * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the
  18 + * GNU General Public License for more details.
  19 + *
  20 + * You should have received a copy of the GNU General Public License
  21 + * along with this program; if not, write to the Free Software
  22 + * Foundation, Inc., 59 Temple Place, Suite 330, Boston, MA 02111-1307 USA
  23 + */
  24 +
  25 +#include <linux/module.h>
  26 +#include <linux/i2c.h>
  27 +#include <linux/interrupt.h>
  28 +#include <linux/sched.h>
  29 +#include <linux/mutex.h>
  30 +#include <linux/delay.h>
  31 +#include <linux/input.h>
  32 +#include <linux/leds.h>
  33 +#include <linux/i2c/lm8323.h>
  34 +
  35 +/* Commands to send to the chip. */
  36 +#define LM8323_CMD_READ_ID 0x80 /* Read chip ID. */
  37 +#define LM8323_CMD_WRITE_CFG 0x81 /* Set configuration item. */
  38 +#define LM8323_CMD_READ_INT 0x82 /* Get interrupt status. */
  39 +#define LM8323_CMD_RESET 0x83 /* Reset, same as external one */
  40 +#define LM8323_CMD_WRITE_PORT_SEL 0x85 /* Set GPIO in/out. */
  41 +#define LM8323_CMD_WRITE_PORT_STATE 0x86 /* Set GPIO pullup. */
  42 +#define LM8323_CMD_READ_PORT_SEL 0x87 /* Get GPIO in/out. */
  43 +#define LM8323_CMD_READ_PORT_STATE 0x88 /* Get GPIO pullup. */
  44 +#define LM8323_CMD_READ_FIFO 0x89 /* Read byte from FIFO. */
  45 +#define LM8323_CMD_RPT_READ_FIFO 0x8a /* Read FIFO (no increment). */
  46 +#define LM8323_CMD_SET_ACTIVE 0x8b /* Set active time. */
  47 +#define LM8323_CMD_READ_ERR 0x8c /* Get error status. */
  48 +#define LM8323_CMD_READ_ROTATOR 0x8e /* Read rotator status. */
  49 +#define LM8323_CMD_SET_DEBOUNCE 0x8f /* Set debouncing time. */
  50 +#define LM8323_CMD_SET_KEY_SIZE 0x90 /* Set keypad size. */
  51 +#define LM8323_CMD_READ_KEY_SIZE 0x91 /* Get keypad size. */
  52 +#define LM8323_CMD_READ_CFG 0x92 /* Get configuration item. */
  53 +#define LM8323_CMD_WRITE_CLOCK 0x93 /* Set clock config. */
  54 +#define LM8323_CMD_READ_CLOCK 0x94 /* Get clock config. */
  55 +#define LM8323_CMD_PWM_WRITE 0x95 /* Write PWM script. */
  56 +#define LM8323_CMD_START_PWM 0x96 /* Start PWM engine. */
  57 +#define LM8323_CMD_STOP_PWM 0x97 /* Stop PWM engine. */
  58 +
  59 +/* Interrupt status. */
  60 +#define INT_KEYPAD 0x01 /* Key event. */
  61 +#define INT_ROTATOR 0x02 /* Rotator event. */
  62 +#define INT_ERROR 0x08 /* Error: use CMD_READ_ERR. */
  63 +#define INT_NOINIT 0x10 /* Lost configuration. */
  64 +#define INT_PWM1 0x20 /* PWM1 stopped. */
  65 +#define INT_PWM2 0x40 /* PWM2 stopped. */
  66 +#define INT_PWM3 0x80 /* PWM3 stopped. */
  67 +
  68 +/* Errors (signalled by INT_ERROR, read with CMD_READ_ERR). */
  69 +#define ERR_BADPAR 0x01 /* Bad parameter. */
  70 +#define ERR_CMDUNK 0x02 /* Unknown command. */
  71 +#define ERR_KEYOVR 0x04 /* Too many keys pressed. */
  72 +#define ERR_FIFOOVER 0x40 /* FIFO overflow. */
  73 +
  74 +/* Configuration keys (CMD_{WRITE,READ}_CFG). */
  75 +#define CFG_MUX1SEL 0x01 /* Select MUX1_OUT input. */
  76 +#define CFG_MUX1EN 0x02 /* Enable MUX1_OUT. */
  77 +#define CFG_MUX2SEL 0x04 /* Select MUX2_OUT input. */
  78 +#define CFG_MUX2EN 0x08 /* Enable MUX2_OUT. */
  79 +#define CFG_PSIZE 0x20 /* Package size (must be 0). */
  80 +#define CFG_ROTEN 0x40 /* Enable rotator. */
  81 +
  82 +/* Clock settings (CMD_{WRITE,READ}_CLOCK). */
  83 +#define CLK_RCPWM_INTERNAL 0x00
  84 +#define CLK_RCPWM_EXTERNAL 0x03
  85 +#define CLK_SLOWCLKEN 0x08 /* Enable 32.768kHz clock. */
  86 +#define CLK_SLOWCLKOUT 0x40 /* Enable slow pulse output. */
  87 +
  88 +/* The possible addresses corresponding to CONFIG1 and CONFIG2 pin wirings. */
  89 +#define LM8323_I2C_ADDR00 (0x84 >> 1) /* 1000 010x */
  90 +#define LM8323_I2C_ADDR01 (0x86 >> 1) /* 1000 011x */
  91 +#define LM8323_I2C_ADDR10 (0x88 >> 1) /* 1000 100x */
  92 +#define LM8323_I2C_ADDR11 (0x8A >> 1) /* 1000 101x */
  93 +
  94 +/* Key event fifo length */
  95 +#define LM8323_FIFO_LEN 15
  96 +
  97 +/* Commands for PWM engine; feed in with PWM_WRITE. */
  98 +/* Load ramp counter from duty cycle field (range 0 - 0xff). */
  99 +#define PWM_SET(v) (0x4000 | ((v) & 0xff))
  100 +/* Go to start of script. */
  101 +#define PWM_GOTOSTART 0x0000
  102 +/*
  103 + * Stop engine (generates interrupt). If reset is 1, clear the program
  104 + * counter, else leave it.
  105 + */
  106 +#define PWM_END(reset) (0xc000 | (!!(reset) << 11))
  107 +/*
  108 + * Ramp. If s is 1, divide clock by 512, else divide clock by 16.
  109 + * Take t clock scales (up to 63) per step, for n steps (up to 126).
  110 + * If u is set, ramp up, else ramp down.
  111 + */
  112 +#define PWM_RAMP(s, t, n, u) ((!!(s) << 14) | ((t) & 0x3f) << 8 | \
  113 + ((n) & 0x7f) | ((u) ? 0 : 0x80))
  114 +/*
  115 + * Loop (i.e. jump back to pos) for a given number of iterations (up to 63).
  116 + * If cnt is zero, execute until PWM_END is encountered.
  117 + */
  118 +#define PWM_LOOP(cnt, pos) (0xa000 | (((cnt) & 0x3f) << 7) | \
  119 + ((pos) & 0x3f))
  120 +/*
  121 + * Wait for trigger. Argument is a mask of channels, shifted by the channel
  122 + * number, e.g. 0xa for channels 3 and 1. Note that channels are numbered
  123 + * from 1, not 0.
  124 + */
  125 +#define PWM_WAIT_TRIG(chans) (0xe000 | (((chans) & 0x7) << 6))
  126 +/* Send trigger. Argument is same as PWM_WAIT_TRIG. */
  127 +#define PWM_SEND_TRIG(chans) (0xe000 | ((chans) & 0x7))
  128 +
  129 +struct lm8323_pwm {
  130 + int id;
  131 + int fade_time;
  132 + int brightness;
  133 + int desired_brightness;
  134 + bool enabled;
  135 + bool running;
  136 + /* pwm lock */
  137 + struct mutex lock;
  138 + struct work_struct work;
  139 + struct led_classdev cdev;
  140 + struct lm8323_chip *chip;
  141 +};
  142 +
  143 +struct lm8323_chip {
  144 + /* device lock */
  145 + struct mutex lock;
  146 + struct i2c_client *client;
  147 + struct work_struct work;
  148 + struct input_dev *idev;
  149 + bool kp_enabled;
  150 + bool pm_suspend;
  151 + unsigned keys_down;
  152 + char phys[32];
  153 + unsigned short keymap[LM8323_KEYMAP_SIZE];
  154 + int size_x;
  155 + int size_y;
  156 + int debounce_time;
  157 + int active_time;
  158 + struct lm8323_pwm pwm[LM8323_NUM_PWMS];
  159 +};
  160 +
  161 +#define client_to_lm8323(c) container_of(c, struct lm8323_chip, client)
  162 +#define dev_to_lm8323(d) container_of(d, struct lm8323_chip, client->dev)
  163 +#define work_to_lm8323(w) container_of(w, struct lm8323_chip, work)
  164 +#define cdev_to_pwm(c) container_of(c, struct lm8323_pwm, cdev)
  165 +#define work_to_pwm(w) container_of(w, struct lm8323_pwm, work)
  166 +
  167 +#define LM8323_MAX_DATA 8
  168 +
  169 +/*
  170 + * To write, we just access the chip's address in write mode, and dump the
  171 + * command and data out on the bus. The command byte and data are taken as
  172 + * sequential u8s out of varargs, to a maximum of LM8323_MAX_DATA.
  173 + */
  174 +static int lm8323_write(struct lm8323_chip *lm, int len, ...)
  175 +{
  176 + int ret, i;
  177 + va_list ap;
  178 + u8 data[LM8323_MAX_DATA];
  179 +
  180 + va_start(ap, len);
  181 +
  182 + if (unlikely(len > LM8323_MAX_DATA)) {
  183 + dev_err(&lm->client->dev, "tried to send %d bytes\n", len);
  184 + va_end(ap);
  185 + return 0;
  186 + }
  187 +
  188 + for (i = 0; i < len; i++)
  189 + data[i] = va_arg(ap, int);
  190 +
  191 + va_end(ap);
  192 +
  193 + /*
  194 + * If the host is asleep while we send the data, we can get a NACK
  195 + * back while it wakes up, so try again, once.
  196 + */
  197 + ret = i2c_master_send(lm->client, data, len);
  198 + if (unlikely(ret == -EREMOTEIO))
  199 + ret = i2c_master_send(lm->client, data, len);
  200 + if (unlikely(ret != len))
  201 + dev_err(&lm->client->dev, "sent %d bytes of %d total\n",
  202 + len, ret);
  203 +
  204 + return ret;
  205 +}
  206 +
  207 +/*
  208 + * To read, we first send the command byte to the chip and end the transaction,
  209 + * then access the chip in read mode, at which point it will send the data.
  210 + */
  211 +static int lm8323_read(struct lm8323_chip *lm, u8 cmd, u8 *buf, int len)
  212 +{
  213 + int ret;
  214 +
  215 + /*
  216 + * If the host is asleep while we send the byte, we can get a NACK
  217 + * back while it wakes up, so try again, once.
  218 + */
  219 + ret = i2c_master_send(lm->client, &cmd, 1);
  220 + if (unlikely(ret == -EREMOTEIO))
  221 + ret = i2c_master_send(lm->client, &cmd, 1);
  222 + if (unlikely(ret != 1)) {
  223 + dev_err(&lm->client->dev, "sending read cmd 0x%02x failed\n",
  224 + cmd);
  225 + return 0;
  226 + }
  227 +
  228 + ret = i2c_master_recv(lm->client, buf, len);
  229 + if (unlikely(ret != len))
  230 + dev_err(&lm->client->dev, "wanted %d bytes, got %d\n",
  231 + len, ret);
  232 +
  233 + return ret;
  234 +}
  235 +
  236 +/*
  237 + * Set the chip active time (idle time before it enters halt).
  238 + */
  239 +static void lm8323_set_active_time(struct lm8323_chip *lm, int time)
  240 +{
  241 + lm8323_write(lm, 2, LM8323_CMD_SET_ACTIVE, time >> 2);
  242 +}
  243 +
  244 +/*
  245 + * The signals are AT-style: the low 7 bits are the keycode, and the top
  246 + * bit indicates the state (1 for down, 0 for up).
  247 + */
  248 +static inline u8 lm8323_whichkey(u8 event)
  249 +{
  250 + return event & 0x7f;
  251 +}
  252 +
  253 +static inline int lm8323_ispress(u8 event)
  254 +{
  255 + return (event & 0x80) ? 1 : 0;
  256 +}
  257 +
  258 +static void process_keys(struct lm8323_chip *lm)
  259 +{
  260 + u8 event;
  261 + u8 key_fifo[LM8323_FIFO_LEN + 1];
  262 + int old_keys_down = lm->keys_down;
  263 + int ret;
  264 + int i = 0;
  265 +
  266 + /*
  267 + * Read all key events from the FIFO at once. Next READ_FIFO clears the
  268 + * FIFO even if we didn't read all events previously.
  269 + */
  270 + ret = lm8323_read(lm, LM8323_CMD_READ_FIFO, key_fifo, LM8323_FIFO_LEN);
  271 +
  272 + if (ret < 0) {
  273 + dev_err(&lm->client->dev, "Failed reading fifo \n");
  274 + return;
  275 + }
  276 + key_fifo[ret] = 0;
  277 +
  278 + while ((event = key_fifo[i++])) {
  279 + u8 key = lm8323_whichkey(event);
  280 + int isdown = lm8323_ispress(event);
  281 + unsigned short keycode = lm->keymap[key];
  282 +
  283 + dev_vdbg(&lm->client->dev, "key 0x%02x %s\n",
  284 + key, isdown ? "down" : "up");
  285 +
  286 + if (lm->kp_enabled) {
  287 + input_event(lm->idev, EV_MSC, MSC_SCAN, key);
  288 + input_report_key(lm->idev, keycode, isdown);
  289 + input_sync(lm->idev);
  290 + }
  291 +
  292 + if (isdown)
  293 + lm->keys_down++;
  294 + else
  295 + lm->keys_down--;
  296 + }
  297 +
  298 + /*
  299 + * Errata: We need to ensure that the chip never enters halt mode
  300 + * during a keypress, so set active time to 0. When it's released,
  301 + * we can enter halt again, so set the active time back to normal.
  302 + */
  303 + if (!old_keys_down && lm->keys_down)
  304 + lm8323_set_active_time(lm, 0);
  305 + if (old_keys_down && !lm->keys_down)
  306 + lm8323_set_active_time(lm, lm->active_time);
  307 +}
  308 +
  309 +static void lm8323_process_error(struct lm8323_chip *lm)
  310 +{
  311 + u8 error;
  312 +
  313 + if (lm8323_read(lm, LM8323_CMD_READ_ERR, &error, 1) == 1) {
  314 + if (error & ERR_FIFOOVER)
  315 + dev_vdbg(&lm->client->dev, "fifo overflow!\n");
  316 + if (error & ERR_KEYOVR)
  317 + dev_vdbg(&lm->client->dev,
  318 + "more than two keys pressed\n");
  319 + if (error & ERR_CMDUNK)
  320 + dev_vdbg(&lm->client->dev,
  321 + "unknown command submitted\n");
  322 + if (error & ERR_BADPAR)
  323 + dev_vdbg(&lm->client->dev, "bad command parameter\n");
  324 + }
  325 +}
  326 +
  327 +static void lm8323_reset(struct lm8323_chip *lm)
  328 +{
  329 + /* The docs say we must pass 0xAA as the data byte. */
  330 + lm8323_write(lm, 2, LM8323_CMD_RESET, 0xAA);
  331 +}
  332 +
  333 +static int lm8323_configure(struct lm8323_chip *lm)
  334 +{
  335 + int keysize = (lm->size_x << 4) | lm->size_y;
  336 + int clock = (CLK_SLOWCLKEN | CLK_RCPWM_EXTERNAL);
  337 + int debounce = lm->debounce_time >> 2;
  338 + int active = lm->active_time >> 2;
  339 +
  340 + /*
  341 + * Active time must be greater than the debounce time: if it's
  342 + * a close-run thing, give ourselves a 12ms buffer.
  343 + */
  344 + if (debounce >= active)
  345 + active = debounce + 3;
  346 +
  347 + lm8323_write(lm, 2, LM8323_CMD_WRITE_CFG, 0);
  348 + lm8323_write(lm, 2, LM8323_CMD_WRITE_CLOCK, clock);
  349 + lm8323_write(lm, 2, LM8323_CMD_SET_KEY_SIZE, keysize);
  350 + lm8323_set_active_time(lm, lm->active_time);
  351 + lm8323_write(lm, 2, LM8323_CMD_SET_DEBOUNCE, debounce);
  352 + lm8323_write(lm, 3, LM8323_CMD_WRITE_PORT_STATE, 0xff, 0xff);
  353 + lm8323_write(lm, 3, LM8323_CMD_WRITE_PORT_SEL, 0, 0);
  354 +
  355 + /*
  356 + * Not much we can do about errors at this point, so just hope
  357 + * for the best.
  358 + */
  359 +
  360 + return 0;
  361 +}
  362 +
  363 +static void pwm_done(struct lm8323_pwm *pwm)
  364 +{
  365 + mutex_lock(&pwm->lock);
  366 + pwm->running = false;
  367 + if (pwm->desired_brightness != pwm->brightness)
  368 + schedule_work(&pwm->work);
  369 + mutex_unlock(&pwm->lock);
  370 +}
  371 +
  372 +/*
  373 + * Bottom half: handle the interrupt by posting key events, or dealing with
  374 + * errors appropriately.
  375 + */
  376 +static void lm8323_work(struct work_struct *work)
  377 +{
  378 + struct lm8323_chip *lm = work_to_lm8323(work);
  379 + u8 ints;
  380 + int i;
  381 +
  382 + mutex_lock(&lm->lock);
  383 +
  384 + while ((lm8323_read(lm, LM8323_CMD_READ_INT, &ints, 1) == 1) && ints) {
  385 + if (likely(ints & INT_KEYPAD))
  386 + process_keys(lm);
  387 + if (ints & INT_ROTATOR) {
  388 + /* We don't currently support the rotator. */
  389 + dev_vdbg(&lm->client->dev, "rotator fired\n");
  390 + }
  391 + if (ints & INT_ERROR) {
  392 + dev_vdbg(&lm->client->dev, "error!\n");
  393 + lm8323_process_error(lm);
  394 + }
  395 + if (ints & INT_NOINIT) {
  396 + dev_err(&lm->client->dev, "chip lost config; "
  397 + "reinitialising\n");
  398 + lm8323_configure(lm);
  399 + }
  400 + for (i = 0; i < LM8323_NUM_PWMS; i++) {
  401 + if (ints & (1 << (INT_PWM1 + i))) {
  402 + dev_vdbg(&lm->client->dev,
  403 + "pwm%d engine completed\n", i);
  404 + pwm_done(&lm->pwm[i]);
  405 + }
  406 + }
  407 + }
  408 +
  409 + mutex_unlock(&lm->lock);
  410 +}
  411 +
  412 +/*
  413 + * We cannot use I2C in interrupt context, so we just schedule work.
  414 + */
  415 +static irqreturn_t lm8323_irq(int irq, void *data)
  416 +{
  417 + struct lm8323_chip *lm = data;
  418 +
  419 + schedule_work(&lm->work);
  420 +
  421 + return IRQ_HANDLED;
  422 +}
  423 +
  424 +/*
  425 + * Read the chip ID.
  426 + */
  427 +static int lm8323_read_id(struct lm8323_chip *lm, u8 *buf)
  428 +{
  429 + int bytes;
  430 +
  431 + bytes = lm8323_read(lm, LM8323_CMD_READ_ID, buf, 2);
  432 + if (unlikely(bytes != 2))
  433 + return -EIO;
  434 +
  435 + return 0;
  436 +}
  437 +
  438 +static void lm8323_write_pwm_one(struct lm8323_pwm *pwm, int pos, u16 cmd)
  439 +{
  440 + lm8323_write(pwm->chip, 4, LM8323_CMD_PWM_WRITE, (pos << 2) | pwm->id,
  441 + (cmd & 0xff00) >> 8, cmd & 0x00ff);
  442 +}
  443 +
  444 +/*
  445 + * Write a script into a given PWM engine, concluding with PWM_END.
  446 + * If 'kill' is nonzero, the engine will be shut down at the end
  447 + * of the script, producing a zero output. Otherwise the engine
  448 + * will be kept running at the final PWM level indefinitely.
  449 + */
  450 +static void lm8323_write_pwm(struct lm8323_pwm *pwm, int kill,
  451 + int len, const u16 *cmds)
  452 +{
  453 + int i;
  454 +
  455 + for (i = 0; i < len; i++)
  456 + lm8323_write_pwm_one(pwm, i, cmds[i]);
  457 +
  458 + lm8323_write_pwm_one(pwm, i++, PWM_END(kill));
  459 + lm8323_write(pwm->chip, 2, LM8323_CMD_START_PWM, pwm->id);
  460 + pwm->running = true;
  461 +}
  462 +
  463 +static void lm8323_pwm_work(struct work_struct *work)
  464 +{
  465 + struct lm8323_pwm *pwm = work_to_pwm(work);
  466 + int div512, perstep, steps, hz, up, kill;
  467 + u16 pwm_cmds[3];
  468 + int num_cmds = 0;
  469 +
  470 + mutex_lock(&pwm->lock);
  471 +
  472 + /*
  473 + * Do nothing if we're already at the requested level,
  474 + * or previous setting is not yet complete. In the latter
  475 + * case we will be called again when the previous PWM script
  476 + * finishes.
  477 + */
  478 + if (pwm->running || pwm->desired_brightness == pwm->brightness)
  479 + goto out;
  480 +
  481 + kill = (pwm->desired_brightness == 0);
  482 + up = (pwm->desired_brightness > pwm->brightness);
  483 + steps = abs(pwm->desired_brightness - pwm->brightness);
  484 +
  485 + /*
  486 + * Convert time (in ms) into a divisor (512 or 16 on a refclk of
  487 + * 32768Hz), and number of ticks per step.
  488 + */
  489 + if ((pwm->fade_time / steps) > (32768 / 512)) {
  490 + div512 = 1;
  491 + hz = 32768 / 512;
  492 + } else {
  493 + div512 = 0;
  494 + hz = 32768 / 16;
  495 + }
  496 +
  497 + perstep = (hz * pwm->fade_time) / (steps * 1000);
  498 +
  499 + if (perstep == 0)
  500 + perstep = 1;
  501 + else if (perstep > 63)
  502 + perstep = 63;
  503 +
  504 + while (steps) {
  505 + int s;
  506 +
  507 + s = min(126, steps);
  508 + pwm_cmds[num_cmds++] = PWM_RAMP(div512, perstep, s, up);
  509 + steps -= s;
  510 + }
  511 +
  512 + lm8323_write_pwm(pwm, kill, num_cmds, pwm_cmds);
  513 + pwm->brightness = pwm->desired_brightness;
  514 +
  515 + out:
  516 + mutex_unlock(&pwm->lock);
  517 +}
  518 +
  519 +static void lm8323_pwm_set_brightness(struct led_classdev *led_cdev,
  520 + enum led_brightness brightness)
  521 +{
  522 + struct lm8323_pwm *pwm = cdev_to_pwm(led_cdev);
  523 + struct lm8323_chip *lm = pwm->chip;
  524 +
  525 + mutex_lock(&pwm->lock);
  526 + pwm->desired_brightness = brightness;
  527 + mutex_unlock(&pwm->lock);
  528 +
  529 + if (in_interrupt()) {
  530 + schedule_work(&pwm->work);
  531 + } else {
  532 + /*
  533 + * Schedule PWM work as usual unless we are going into suspend
  534 + */
  535 + mutex_lock(&lm->lock);
  536 + if (likely(!lm->pm_suspend))
  537 + schedule_work(&pwm->work);
  538 + else
  539 + lm8323_pwm_work(&pwm->work);
  540 + mutex_unlock(&lm->lock);
  541 + }
  542 +}
  543 +
  544 +static ssize_t lm8323_pwm_show_time(struct device *dev,
  545 + struct device_attribute *attr, char *buf)
  546 +{
  547 + struct led_classdev *led_cdev = dev_get_drvdata(dev);
  548 + struct lm8323_pwm *pwm = cdev_to_pwm(led_cdev);
  549 +
  550 + return sprintf(buf, "%d\n", pwm->fade_time);
  551 +}
  552 +
  553 +static ssize_t lm8323_pwm_store_time(struct device *dev,
  554 + struct device_attribute *attr, const char *buf, size_t len)
  555 +{
  556 + struct led_classdev *led_cdev = dev_get_drvdata(dev);
  557 + struct lm8323_pwm *pwm = cdev_to_pwm(led_cdev);
  558 + int ret;
  559 + unsigned long time;
  560 +
  561 + ret = strict_strtoul(buf, 10, &time);
  562 + /* Numbers only, please. */
  563 + if (ret)
  564 + return -EINVAL;
  565 +
  566 + pwm->fade_time = time;
  567 +
  568 + return strlen(buf);
  569 +}
  570 +static DEVICE_ATTR(time, 0644, lm8323_pwm_show_time, lm8323_pwm_store_time);
  571 +
  572 +static int init_pwm(struct lm8323_chip *lm, int id, struct device *dev,
  573 + const char *name)
  574 +{
  575 + struct lm8323_pwm *pwm;
  576 +
  577 + BUG_ON(id > 3);
  578 +
  579 + pwm = &lm->pwm[id - 1];
  580 +
  581 + pwm->id = id;
  582 + pwm->fade_time = 0;
  583 + pwm->brightness = 0;
  584 + pwm->desired_brightness = 0;
  585 + pwm->running = false;
  586 + pwm->enabled = false;
  587 + INIT_WORK(&pwm->work, lm8323_pwm_work);
  588 + mutex_init(&pwm->lock);
  589 + pwm->chip = lm;
  590 +
  591 + if (name) {
  592 + pwm->cdev.name = name;
  593 + pwm->cdev.brightness_set = lm8323_pwm_set_brightness;
  594 + if (led_classdev_register(dev, &pwm->cdev) < 0) {
  595 + dev_err(dev, "couldn't register PWM %d\n", id);
  596 + return -1;
  597 + }
  598 + if (device_create_file(pwm->cdev.dev,
  599 + &dev_attr_time) < 0) {
  600 + dev_err(dev, "couldn't register time attribute\n");
  601 + led_classdev_unregister(&pwm->cdev);
  602 + return -1;
  603 + }
  604 + pwm->enabled = true;
  605 + }
  606 +
  607 + return 0;
  608 +}
  609 +
  610 +static struct i2c_driver lm8323_i2c_driver;
  611 +
  612 +static ssize_t lm8323_show_disable(struct device *dev,
  613 + struct device_attribute *attr, char *buf)
  614 +{
  615 + struct lm8323_chip *lm = dev_get_drvdata(dev);
  616 +
  617 + return sprintf(buf, "%u\n", !lm->kp_enabled);
  618 +}
  619 +
  620 +static ssize_t lm8323_set_disable(struct device *dev,
  621 + struct device_attribute *attr,
  622 + const char *buf, size_t count)
  623 +{
  624 + struct lm8323_chip *lm = dev_get_drvdata(dev);
  625 + int ret;
  626 + unsigned long i;
  627 +
  628 + ret = strict_strtoul(buf, 10, &i);
  629 +
  630 + mutex_lock(&lm->lock);
  631 + lm->kp_enabled = !i;
  632 + mutex_unlock(&lm->lock);
  633 +
  634 + return count;
  635 +}
  636 +static DEVICE_ATTR(disable_kp, 0644, lm8323_show_disable, lm8323_set_disable);
  637 +
  638 +static int __devinit lm8323_probe(struct i2c_client *client,
  639 + const struct i2c_device_id *id)
  640 +{
  641 + struct lm8323_platform_data *pdata = client->dev.platform_data;
  642 + struct input_dev *idev;
  643 + struct lm8323_chip *lm;
  644 + int i, err;
  645 + unsigned long tmo;
  646 + u8 data[2];
  647 +
  648 + if (!pdata || !pdata->size_x || !pdata->size_y) {
  649 + dev_err(&client->dev, "missing platform_data\n");
  650 + return -EINVAL;
  651 + }
  652 +
  653 + if (pdata->size_x > 8) {
  654 + dev_err(&client->dev, "invalid x size %d specified\n",
  655 + pdata->size_x);
  656 + return -EINVAL;
  657 + }
  658 +
  659 + if (pdata->size_y > 12) {
  660 + dev_err(&client->dev, "invalid y size %d specified\n",
  661 + pdata->size_y);
  662 + return -EINVAL;
  663 + }
  664 +
  665 + lm = kzalloc(sizeof *lm, GFP_KERNEL);
  666 + idev = input_allocate_device();
  667 + if (!lm || !idev) {
  668 + err = -ENOMEM;
  669 + goto fail1;
  670 + }
  671 +
  672 + i2c_set_clientdata(client, lm);
  673 +
  674 + lm->client = client;
  675 + lm->idev = idev;
  676 + mutex_init(&lm->lock);
  677 + INIT_WORK(&lm->work, lm8323_work);
  678 +
  679 + lm->size_x = pdata->size_x;
  680 + lm->size_y = pdata->size_y;
  681 + dev_vdbg(&client->dev, "Keypad size: %d x %d\n",
  682 + lm->size_x, lm->size_y);
  683 +
  684 + lm->debounce_time = pdata->debounce_time;
  685 + lm->active_time = pdata->active_time;
  686 +
  687 + lm8323_reset(lm);
  688 +
  689 + /* Nothing's set up to service the IRQ yet, so just spin for max.
  690 + * 100ms until we can configure. */
  691 + tmo = jiffies + msecs_to_jiffies(100);
  692 + while (lm8323_read(lm, LM8323_CMD_READ_INT, data, 1) == 1) {
  693 + if (data[0] & INT_NOINIT)
  694 + break;
  695 +
  696 + if (time_after(jiffies, tmo)) {
  697 + dev_err(&client->dev,
  698 + "timeout waiting for initialisation\n");
  699 + break;
  700 + }
  701 +
  702 + msleep(1);
  703 + }
  704 +
  705 + lm8323_configure(lm);
  706 +
  707 + /* If a true probe check the device */
  708 + if (lm8323_read_id(lm, data) != 0) {
  709 + dev_err(&client->dev, "device not found\n");
  710 + err = -ENODEV;
  711 + goto fail1;
  712 + }
  713 +
  714 + for (i = 0; i < LM8323_NUM_PWMS; i++) {
  715 + err = init_pwm(lm, i + 1, &client->dev, pdata->pwm_names[i]);
  716 + if (err < 0)
  717 + goto fail2;
  718 + }
  719 +
  720 + lm->kp_enabled = true;
  721 + err = device_create_file(&client->dev, &dev_attr_disable_kp);
  722 + if (err < 0)
  723 + goto fail2;
  724 +
  725 + idev->name = pdata->name ? : "LM8323 keypad";
  726 + snprintf(lm->phys, sizeof(lm->phys),
  727 + "%s/input-kp", dev_name(&client->dev));
  728 + idev->phys = lm->phys;
  729 +
  730 + idev->evbit[0] = BIT(EV_KEY) | BIT(EV_MSC);
  731 + __set_bit(MSC_SCAN, idev->mscbit);
  732 + for (i = 0; i < LM8323_KEYMAP_SIZE; i++) {
  733 + __set_bit(pdata->keymap[i], idev->keybit);
  734 + lm->keymap[i] = pdata->keymap[i];
  735 + }
  736 + __clear_bit(KEY_RESERVED, idev->keybit);
  737 +
  738 + if (pdata->repeat)
  739 + __set_bit(EV_REP, idev->evbit);
  740 +
  741 + err = input_register_device(idev);
  742 + if (err) {
  743 + dev_dbg(&client->dev, "error registering input device\n");
  744 + goto fail3;
  745 + }
  746 +
  747 + err = request_irq(client->irq, lm8323_irq,
  748 + IRQF_TRIGGER_FALLING | IRQF_DISABLED,
  749 + "lm8323", lm);
  750 + if (err) {
  751 + dev_err(&client->dev, "could not get IRQ %d\n", client->irq);
  752 + goto fail4;
  753 + }
  754 +
  755 + device_init_wakeup(&client->dev, 1);
  756 + enable_irq_wake(client->irq);
  757 +
  758 + return 0;
  759 +
  760 +fail4:
  761 + input_unregister_device(idev);
  762 + idev = NULL;
  763 +fail3:
  764 + device_remove_file(&client->dev, &dev_attr_disable_kp);
  765 +fail2:
  766 + while (--i >= 0)
  767 + if (lm->pwm[i].enabled)
  768 + led_classdev_unregister(&lm->pwm[i].cdev);
  769 +fail1:
  770 + input_free_device(idev);
  771 + kfree(lm);
  772 + return err;
  773 +}
  774 +
  775 +static int __devexit lm8323_remove(struct i2c_client *client)
  776 +{
  777 + struct lm8323_chip *lm = i2c_get_clientdata(client);
  778 + int i;
  779 +
  780 + disable_irq_wake(client->irq);
  781 + free_irq(client->irq, lm);
  782 + cancel_work_sync(&lm->work);
  783 +
  784 + input_unregister_device(lm->idev);
  785 +
  786 + device_remove_file(&lm->client->dev, &dev_attr_disable_kp);
  787 +
  788 + for (i = 0; i < 3; i++)
  789 + if (lm->pwm[i].enabled)
  790 + led_classdev_unregister(&lm->pwm[i].cdev);
  791 +
  792 + kfree(lm);
  793 +
  794 + return 0;
  795 +}
  796 +
  797 +#ifdef CONFIG_PM
  798 +/*
  799 + * We don't need to explicitly suspend the chip, as it already switches off
  800 + * when there's no activity.
  801 + */
  802 +static int lm8323_suspend(struct i2c_client *client, pm_message_t mesg)
  803 +{
  804 + struct lm8323_chip *lm = i2c_get_clientdata(client);
  805 + int i;
  806 +
  807 + set_irq_wake(client->irq, 0);
  808 + disable_irq(client->irq);
  809 +
  810 + mutex_lock(&lm->lock);
  811 + lm->pm_suspend = true;
  812 + mutex_unlock(&lm->lock);
  813 +
  814 + for (i = 0; i < 3; i++)
  815 + if (lm->pwm[i].enabled)
  816 + led_classdev_suspend(&lm->pwm[i].cdev);
  817 +
  818 + return 0;
  819 +}
  820 +
  821 +static int lm8323_resume(struct i2c_client *client)
  822 +{
  823 + struct lm8323_chip *lm = i2c_get_clientdata(client);
  824 + int i;
  825 +
  826 + mutex_lock(&lm->lock);
  827 + lm->pm_suspend = false;
  828 + mutex_unlock(&lm->lock);
  829 +
  830 + for (i = 0; i < 3; i++)
  831 + if (lm->pwm[i].enabled)
  832 + led_classdev_resume(&lm->pwm[i].cdev);
  833 +
  834 + enable_irq(client->irq);
  835 + set_irq_wake(client->irq, 1);
  836 +
  837 + return 0;
  838 +}
  839 +#else
  840 +#define lm8323_suspend NULL
  841 +#define lm8323_resume NULL
  842 +#endif
  843 +
  844 +static const struct i2c_device_id lm8323_id[] = {
  845 + { "lm8323", 0 },
  846 + { }
  847 +};
  848 +
  849 +static struct i2c_driver lm8323_i2c_driver = {
  850 + .driver = {
  851 + .name = "lm8323",
  852 + },
  853 + .probe = lm8323_probe,
  854 + .remove = __devexit_p(lm8323_remove),
  855 + .suspend = lm8323_suspend,
  856 + .resume = lm8323_resume,
  857 + .id_table = lm8323_id,
  858 +};
  859 +MODULE_DEVICE_TABLE(i2c, lm8323_id);
  860 +
  861 +static int __init lm8323_init(void)
  862 +{
  863 + return i2c_add_driver(&lm8323_i2c_driver);
  864 +}
  865 +module_init(lm8323_init);
  866 +
  867 +static void __exit lm8323_exit(void)
  868 +{
  869 + i2c_del_driver(&lm8323_i2c_driver);
  870 +}
  871 +module_exit(lm8323_exit);
  872 +
  873 +MODULE_AUTHOR("Timo O. Karjalainen <timo.o.karjalainen@nokia.com>");
  874 +MODULE_AUTHOR("Daniel Stone");
  875 +MODULE_AUTHOR("Felipe Balbi <felipe.balbi@nokia.com>");
  876 +MODULE_DESCRIPTION("LM8323 keypad driver");
  877 +MODULE_LICENSE("GPL");
include/linux/i2c/lm8323.h
  1 +/*
  2 + * lm8323.h - Configuration for LM8323 keypad driver.
  3 + *
  4 + * This program is free software; you can redistribute it and/or modify
  5 + * it under the terms of the GNU General Public License as published by
  6 + * the Free Software Foundation (version 2 of the License only).
  7 + *
  8 + * This program is distributed in the hope that it will be useful,
  9 + * but WITHOUT ANY WARRANTY; without even the implied warranty of
  10 + * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the
  11 + * GNU General Public License for more details.
  12 + *
  13 + * You should have received a copy of the GNU General Public License
  14 + * along with this program; if not, write to the Free Software
  15 + * Foundation, Inc., 59 Temple Place, Suite 330, Boston, MA 02111-1307 USA
  16 + */
  17 +
  18 +#ifndef __LINUX_LM8323_H
  19 +#define __LINUX_LM8323_H
  20 +
  21 +#include <linux/types.h>
  22 +
  23 +/*
  24 + * Largest keycode that the chip can send, plus one,
  25 + * so keys can be mapped directly at the index of the
  26 + * LM8323 keycode instead of subtracting one.
  27 + */
  28 +#define LM8323_KEYMAP_SIZE (0x7f + 1)
  29 +
  30 +#define LM8323_NUM_PWMS 3
  31 +
  32 +struct lm8323_platform_data {
  33 + int debounce_time; /* Time to watch for key bouncing, in ms. */
  34 + int active_time; /* Idle time until sleep, in ms. */
  35 +
  36 + int size_x;
  37 + int size_y;
  38 + bool repeat;
  39 + const unsigned short *keymap;
  40 +
  41 + const char *pwm_names[LM8323_NUM_PWMS];
  42 +
  43 + const char *name; /* Device name. */
  44 +};
  45 +
  46 +#endif /* __LINUX_LM8323_H */