diff options
Diffstat (limited to 'target/linux/s3c24xx/files-2.6.31/drivers/power/hdq.c')
| -rw-r--r-- | target/linux/s3c24xx/files-2.6.31/drivers/power/hdq.c | 515 |
1 files changed, 0 insertions, 515 deletions
diff --git a/target/linux/s3c24xx/files-2.6.31/drivers/power/hdq.c b/target/linux/s3c24xx/files-2.6.31/drivers/power/hdq.c deleted file mode 100644 index f03fabf..0000000 --- a/target/linux/s3c24xx/files-2.6.31/drivers/power/hdq.c +++ /dev/null @@ -1,515 +0,0 @@ -/* - * HDQ generic GPIO bitbang driver using FIQ - * - * (C) 2006-2007 by Openmoko, Inc. - * Author: Andy Green <andy@openmoko.com> - * All rights reserved. - * - * 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/init.h> -#include <linux/delay.h> -#include <linux/platform_device.h> -#include <linux/hdq.h> - -#define HDQ_READ 0 -#define HDQ_WRITE 0x80 - -enum hdq_bitbang_states { - HDQB_IDLE = 0, - HDQB_TX_BREAK, - HDQB_TX_BREAK_RECOVERY, - HDQB_ADS_CALC, - HDQB_ADS_LOW, - HDQB_ADS_HIGH, - HDQB_WAIT_RX, - HDQB_DATA_RX_LOW, - HDQB_DATA_RX_HIGH, - HDQB_WAIT_TX, -}; - -static struct hdq_priv { - u8 hdq_probed; /* nonzero after HDQ driver probed */ - struct mutex hdq_lock; /* if you want to use hdq, you have to take lock */ - unsigned long hdq_gpio_pin; /* GTA02 = GPD14 which pin to meddle with */ - u8 hdq_ads; /* b7..b6 = register address, b0 = r/w */ - u8 hdq_tx_data; /* data to tx for write action */ - u8 hdq_rx_data; /* data received in read action */ - u8 hdq_request_ctr; /* incremented by "user" to request a transfer */ - u8 hdq_transaction_ctr; /* incremented after each transfer */ - u8 hdq_error; /* 0 = no error */ - u8 hdq_ctr; - u8 hdq_ctr2; - u8 hdq_bit; - u8 hdq_shifter; - u8 hdq_tx_data_done; - enum hdq_bitbang_states hdq_state; - int reported_error; - - struct hdq_platform_data *pdata; -} hdq_priv; - - -static void hdq_bad(void) -{ - if (!hdq_priv.reported_error) - printk(KERN_ERR "HDQ error: %d\n", hdq_priv.hdq_error); - hdq_priv.reported_error = 1; -} - -static void hdq_good(void) -{ - if (hdq_priv.reported_error) - printk(KERN_INFO "HDQ responds again\n"); - hdq_priv.reported_error = 0; -} - -int hdq_fiq_handler(void) -{ - if (!hdq_priv.hdq_probed) - return 0; - - switch (hdq_priv.hdq_state) { - case HDQB_IDLE: - if (hdq_priv.hdq_request_ctr == hdq_priv.hdq_transaction_ctr) - break; - hdq_priv.hdq_ctr = 250 / HDQ_SAMPLE_PERIOD_US; - hdq_priv.pdata->gpio_set(0); - hdq_priv.pdata->gpio_dir_out(); - hdq_priv.hdq_tx_data_done = 0; - hdq_priv.hdq_state = HDQB_TX_BREAK; - break; - - case HDQB_TX_BREAK: /* issue low for > 190us */ - if (--hdq_priv.hdq_ctr == 0) { - hdq_priv.hdq_ctr = 60 / HDQ_SAMPLE_PERIOD_US; - hdq_priv.hdq_state = HDQB_TX_BREAK_RECOVERY; - hdq_priv.pdata->gpio_set(1); - } - break; - - case HDQB_TX_BREAK_RECOVERY: /* issue low for > 40us */ - if (--hdq_priv.hdq_ctr) - break; - hdq_priv.hdq_shifter = hdq_priv.hdq_ads; - hdq_priv.hdq_bit = 8; /* 8 bits of ads / rw */ - hdq_priv.hdq_tx_data_done = 0; /* doing ads */ - /* fallthru on last one */ - case HDQB_ADS_CALC: - if (hdq_priv.hdq_shifter & 1) - hdq_priv.hdq_ctr = 50 / HDQ_SAMPLE_PERIOD_US; - else - hdq_priv.hdq_ctr = 120 / HDQ_SAMPLE_PERIOD_US; - /* carefully precompute the other phase length */ - hdq_priv.hdq_ctr2 = (210 - (hdq_priv.hdq_ctr * HDQ_SAMPLE_PERIOD_US)) / - HDQ_SAMPLE_PERIOD_US; - hdq_priv.hdq_state = HDQB_ADS_LOW; - hdq_priv.hdq_shifter >>= 1; - hdq_priv.hdq_bit--; - hdq_priv.pdata->gpio_set(0); - break; - - case HDQB_ADS_LOW: - if (--hdq_priv.hdq_ctr) - break; - hdq_priv.pdata->gpio_set(1); - hdq_priv.hdq_state = HDQB_ADS_HIGH; - break; - - case HDQB_ADS_HIGH: - if (--hdq_priv.hdq_ctr2 > 1) /* account for HDQB_ADS_CALC */ - break; - if (hdq_priv.hdq_bit) { /* more bits to do */ - hdq_priv.hdq_state = HDQB_ADS_CALC; - break; - } - /* no more bits, wait it out until hdq_priv.hdq_ctr2 exhausted */ - if (hdq_priv.hdq_ctr2) - break; - /* ok no more bits and very last state */ - hdq_priv.hdq_ctr = 60 / HDQ_SAMPLE_PERIOD_US; - /* FIXME 0 = read */ - if (hdq_priv.hdq_ads & 0x80) { /* write the byte out */ - /* set delay before payload */ - hdq_priv.hdq_ctr = 300 / HDQ_SAMPLE_PERIOD_US; - /* already high, no need to write */ - hdq_priv.hdq_state = HDQB_WAIT_TX; - break; - } - /* read the next byte */ - hdq_priv.hdq_bit = 8; /* 8 bits of data */ - hdq_priv.hdq_ctr = 2500 / HDQ_SAMPLE_PERIOD_US; - hdq_priv.hdq_state = HDQB_WAIT_RX; - hdq_priv.pdata->gpio_dir_in(); - break; - - case HDQB_WAIT_TX: /* issue low for > 40us */ - if (--hdq_priv.hdq_ctr) - break; - if (!hdq_priv.hdq_tx_data_done) { /* was that the data sent? */ - hdq_priv.hdq_tx_data_done++; - hdq_priv.hdq_shifter = hdq_priv.hdq_tx_data; - hdq_priv.hdq_bit = 8; /* 8 bits of data */ - hdq_priv.hdq_state = HDQB_ADS_CALC; /* start sending */ - break; - } - hdq_priv.hdq_error = 0; - hdq_priv.hdq_transaction_ctr = hdq_priv.hdq_request_ctr; - hdq_priv.hdq_state = HDQB_IDLE; /* all tx is done */ - /* idle in input mode, it's pulled up by 10K */ - hdq_priv.pdata->gpio_dir_in(); - break; - - case HDQB_WAIT_RX: /* wait for battery to talk to us */ - if (hdq_priv.pdata->gpio_get() == 0) { - /* it talks to us! */ - hdq_priv.hdq_ctr2 = 1; - hdq_priv.hdq_bit = 8; /* 8 bits of data */ - /* timeout */ - hdq_priv.hdq_ctr = 500 / HDQ_SAMPLE_PERIOD_US; - hdq_priv.hdq_state = HDQB_DATA_RX_LOW; - break; - } - if (--hdq_priv.hdq_ctr == 0) { /* timed out, error */ - hdq_priv.hdq_error = 1; - hdq_priv.hdq_transaction_ctr = hdq_priv.hdq_request_ctr; - hdq_priv.hdq_state = HDQB_IDLE; /* abort */ - } - break; - - /* - * HDQ basically works by measuring the low time of the bit cell - * 32-50us --> '1', 80 - 145us --> '0' - */ - - case HDQB_DATA_RX_LOW: - if (hdq_priv.pdata->gpio_get()) { - hdq_priv.hdq_rx_data >>= 1; - if (hdq_priv.hdq_ctr2 <= (65 / HDQ_SAMPLE_PERIOD_US)) - hdq_priv.hdq_rx_data |= 0x80; - - if (--hdq_priv.hdq_bit == 0) { - hdq_priv.hdq_error = 0; - hdq_priv.hdq_transaction_ctr = - hdq_priv.hdq_request_ctr; - - hdq_priv.hdq_state = HDQB_IDLE; - } else - hdq_priv.hdq_state = HDQB_DATA_RX_HIGH; - /* timeout */ - hdq_priv.hdq_ctr = 1000 / HDQ_SAMPLE_PERIOD_US; - hdq_priv.hdq_ctr2 = 1; - break; - } - hdq_priv.hdq_ctr2++; - if (--hdq_priv.hdq_ctr) - break; - /* timed out, error */ - hdq_priv.hdq_error = 2; - hdq_priv.hdq_transaction_ctr = hdq_priv.hdq_request_ctr; - hdq_priv.hdq_state = HDQB_IDLE; /* abort */ - break; - - case HDQB_DATA_RX_HIGH: - if (!hdq_priv.pdata->gpio_get()) { - /* it talks to us! */ - hdq_priv.hdq_ctr2 = 1; - /* timeout */ - hdq_priv.hdq_ctr = 400 / HDQ_SAMPLE_PERIOD_US; - hdq_priv.hdq_state = HDQB_DATA_RX_LOW; - break; - } - if (--hdq_priv.hdq_ctr) - break; - /* timed out, error */ - hdq_priv.hdq_error = 3; - hdq_priv.hdq_transaction_ctr = hdq_priv.hdq_request_ctr; - - /* we're in input mode already */ - hdq_priv.hdq_state = HDQB_IDLE; /* abort */ - break; - } - - /* Are we interested in keeping the FIQ source alive ? */ - if (hdq_priv.hdq_state != HDQB_IDLE) - return 1; - else - return 0; -} -static int fiq_busy(void) -{ - int request = (volatile u8)hdq_priv.hdq_request_ctr; - int transact = (volatile u8)hdq_priv.hdq_transaction_ctr; - - - return (request != transact); -} - -int hdq_initialized(void) -{ - return hdq_priv.hdq_probed; -} -EXPORT_SYMBOL_GPL(hdq_initialized); - -int hdq_read(int address) -{ - int count_sleeps = 5; - int ret = -ETIME; - - if (!hdq_priv.hdq_probed) - return -EINVAL; - - mutex_lock(&hdq_priv.hdq_lock); - - hdq_priv.hdq_error = 0; - hdq_priv.hdq_ads = address | HDQ_READ; - hdq_priv.hdq_request_ctr++; - hdq_priv.pdata->kick_fiq(); - /* - * FIQ takes care of it while we block our calling process - * But we're not spinning -- other processes run normally while - * we wait for the result - */ - while (count_sleeps--) { - msleep(10); /* valid transaction always completes in < 10ms */ - - if (fiq_busy()) - continue; - - if (hdq_priv.hdq_error) { - hdq_bad(); - goto done; /* didn't see a response in good time */ - } - hdq_good(); - - ret = hdq_priv.hdq_rx_data; - goto done; - } - -done: - mutex_unlock(&hdq_priv.hdq_lock); - return ret; -} -EXPORT_SYMBOL_GPL(hdq_read); - -int hdq_write(int address, u8 data) -{ - int count_sleeps = 5; - int ret = -ETIME; - - if (!hdq_priv.hdq_probed) - return -EINVAL; - - mutex_lock(&hdq_priv.hdq_lock); - - hdq_priv.hdq_error = 0; - hdq_priv.hdq_ads = address | HDQ_WRITE; - hdq_priv.hdq_tx_data = data; - hdq_priv.hdq_request_ctr++; - hdq_priv.pdata->kick_fiq(); - /* - * FIQ takes care of it while we block our calling process - * But we're not spinning -- other processes run normally while - * we wait for the result - */ - while (count_sleeps--) { - msleep(10); /* valid transaction always completes in < 10ms */ - - if (fiq_busy()) - continue; /* something bad with FIQ */ - - if (hdq_priv.hdq_error) { - hdq_bad(); - goto done; /* didn't see a response in good time */ - } - hdq_good(); - - ret = 0; - goto done; - } - -done: - mutex_unlock(&hdq_priv.hdq_lock); - return ret; -} -EXPORT_SYMBOL_GPL(hdq_write); - -/* sysfs */ - -static ssize_t hdq_sysfs_dump(struct device *dev, struct device_attribute *attr, - char *buf) -{ - int n; - int v; - u8 u8a[128]; /* whole address space for HDQ */ - char *end = buf; - - if (!hdq_priv.hdq_probed) - return -EINVAL; - - /* the dump does not take care about 16 bit regs, because at this - * bus level we don't know about the chip details - */ - for (n = 0; n < sizeof(u8a); n++) { - v = hdq_read(n); - if (v < 0) - goto bail; - u8a[n] = v; - } - - for (n = 0; n < sizeof(u8a); n += 16) { - hex_dump_to_buffer(u8a + n, sizeof(u8a), 16, 1, end, 4096, 0); - end += strlen(end); - *end++ = '\n'; - *end = '\0'; - } - return (end - buf); - -bail: - return sprintf(buf, "ERROR %d\n", v); -} - -/* you write by <address> <data>, eg, "34 128" */ - -#define atoi(str) simple_strtoul(((str != NULL) ? str : ""), NULL, 0) - -static ssize_t hdq_sysfs_write(struct device *dev, - struct device_attribute *attr, - const char *buf, size_t count) -{ - const char *end = buf + count; - int address = atoi(buf); - - if (!hdq_priv.hdq_probed) - return -EINVAL; - - while ((buf != end) && (*buf != ' ')) - buf++; - if (buf >= end) - return 0; - while ((buf < end) && (*buf == ' ')) - buf++; - if (buf >= end) - return 0; - - hdq_write(address, atoi(buf)); - - return count; -} - -static DEVICE_ATTR(dump, 0400, hdq_sysfs_dump, NULL); -static DEVICE_ATTR(write, 0600, NULL, hdq_sysfs_write); - -static struct attribute *hdq_sysfs_entries[] = { - &dev_attr_dump.attr, - &dev_attr_write.attr, - NULL -}; - -static struct attribute_group hdq_attr_group = { - .name = "hdq", - .attrs = hdq_sysfs_entries, -}; - - -#ifdef CONFIG_PM -static int hdq_suspend(struct platform_device *pdev, pm_message_t state) -{ - /* after 18s of this, the battery monitor will also go to sleep */ - hdq_priv.pdata->gpio_dir_in(); - hdq_priv.pdata->disable_fiq(); - return 0; -} - -static int hdq_resume(struct platform_device *pdev) -{ - hdq_priv.pdata->gpio_set(1); - hdq_priv.pdata->gpio_dir_out(); - hdq_priv.pdata->enable_fiq(); - return 0; -} -#endif - -static int __init hdq_probe(struct platform_device *pdev) -{ - struct resource *r = platform_get_resource(pdev, 0, 0); - int ret; - struct hdq_platform_data *pdata = pdev->dev.platform_data; - - if (!r || !pdata) - return -EINVAL; - - platform_set_drvdata(pdev, NULL); - - mutex_init(&hdq_priv.hdq_lock); - - /* set our HDQ comms pin from the platform data */ - hdq_priv.hdq_gpio_pin = r->start; - hdq_priv.pdata = pdata; - - hdq_priv.pdata->gpio_set(1); - hdq_priv.pdata->gpio_dir_out(); - - /* Initialize FIQ */ - if (hdq_priv.pdata->enable_fiq() < 0) { - dev_err(&pdev->dev, "Could not enable FIQ source\n"); - return -EINVAL; - } - - ret = sysfs_create_group(&pdev->dev.kobj, &hdq_attr_group); - if (ret) - return ret; - - hdq_priv.hdq_probed = 1; /* we are ready to do stuff now */ - - /* - * if wanted, users can defer registration of devices - * that depend on HDQ until after we register, and can use our - * device as parent so suspend-resume ordering is correct - */ - if (pdata->attach_child_devices) - (pdata->attach_child_devices)(&pdev->dev); - - hdq_priv.pdata = pdata; - - return 0; -} - -static int hdq_remove(struct platform_device *pdev) -{ - sysfs_remove_group(&pdev->dev.kobj, &hdq_attr_group); - return 0; -} - -static struct platform_driver hdq_driver = { - .probe = hdq_probe, - .remove = hdq_remove, -#ifdef CONFIG_PM - .suspend = hdq_suspend, - .resume = hdq_resume, -#endif - .driver = { - .name = "hdq", - }, -}; - -static int __init hdq_init(void) -{ - return platform_driver_register(&hdq_driver); -} - -static void __exit hdq_exit(void) -{ - platform_driver_unregister(&hdq_driver); -} - -module_init(hdq_init); -module_exit(hdq_exit); - -MODULE_AUTHOR("Andy Green <andy@openmoko.com>"); -MODULE_DESCRIPTION("HDQ driver"); |