From 6d2c293d6578048e7b71e0c44897144f15f350ae Mon Sep 17 00:00:00 2001 From: merging other branches Date: Wed, 26 Nov 2008 16:07:01 +0000 Subject: MERGE-via-balaji-tracking-hist-MERGE-via-stable-tracking-hist-MERGE-via-mokopatches-tracking-via-master-s3c-hsmmc-clean balaji-tracking-hist top was efb2d57c0e0ed62324d79d6c5793fe797c157266 --- drivers/mfd/pcf50606-adc.c | 239 +++++++++++++++++++++++++++++++++++++++++++++ 1 file changed, 239 insertions(+) create mode 100644 drivers/mfd/pcf50606-adc.c (limited to 'drivers/mfd/pcf50606-adc.c') diff --git a/drivers/mfd/pcf50606-adc.c b/drivers/mfd/pcf50606-adc.c new file mode 100644 index 00000000000..68e099ad61c --- /dev/null +++ b/drivers/mfd/pcf50606-adc.c @@ -0,0 +1,239 @@ +/* Philips PCF50606 ADC Driver + * + * (C) 2006-2008 by Openmoko, Inc. + * Author: Balaji Rao + * All rights reserved. + * + * Broken down from monstrous PCF50606 driver mainly by + * Harald Welte, Andy Green and Werner Almesberger + * + * This program is free software; you can redistribute it and/or + * modify it under the terms of the GNU General Public License as + * published by the Free Software Foundation; either version 2 of + * the License, or (at your option) any later version. + * + * This program is distributed in the hope that it will be useful, + * but WITHOUT ANY WARRANTY; without even the implied warranty of + * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the + * GNU General Public License for more details. + * + * You should have received a copy of the GNU General Public License + * along with this program; if not, write to the Free Software + * Foundation, Inc., 59 Temple Place, Suite 330, Boston, + * MA 02111-1307 USA + */ + +#include +#include + +struct pcf50606_adc_request { + int mux; + int avg; + int result; + void (*callback)(struct pcf50606 *, void *, int); + void *callback_param; + + /* Used in case of sync requests */ + struct completion completion; + +}; + +static void adc_read_setup(struct pcf50606 *pcf, + int channel, int avg) +{ + channel &= PCF50606_ADCC2_ADCMUX_MASK; + + /* start ADC conversion of selected channel */ + pcf50606_reg_write(pcf, PCF50606_REG_ADCC2, channel | + PCF50606_ADCC2_ADCSTART | PCF50606_ADCC2_RES_10BIT); + +} + +static void trigger_next_adc_job_if_any(struct pcf50606 *pcf) +{ + int head, tail; + + mutex_lock(&pcf->adc.queue_mutex); + + head = pcf->adc.queue_head; + tail = pcf->adc.queue_tail; + + if (!pcf->adc.queue[head]) + goto out; + + adc_read_setup(pcf, pcf->adc.queue[head]->mux, + pcf->adc.queue[head]->avg); +out: + mutex_unlock(&pcf->adc.queue_mutex); +} + +static int +adc_enqueue_request(struct pcf50606 *pcf, struct pcf50606_adc_request *req) +{ + int head, tail; + + mutex_lock(&pcf->adc.queue_mutex); + head = pcf->adc.queue_head; + tail = pcf->adc.queue_tail; + + if (pcf->adc.queue[tail]) { + mutex_unlock(&pcf->adc.queue_mutex); + return -EBUSY; + } + + pcf->adc.queue[tail] = req; + + pcf->adc.queue_tail = + (tail + 1) & (PCF50606_MAX_ADC_FIFO_DEPTH - 1); + + mutex_unlock(&pcf->adc.queue_mutex); + + trigger_next_adc_job_if_any(pcf); + + return 0; +} + +static void +pcf50606_adc_sync_read_callback(struct pcf50606 *pcf, void *param, int result) +{ + struct pcf50606_adc_request *req; + + /*We know here that the passed param is an adc_request object */ + req = (struct pcf50606_adc_request *)param; + + req->result = result; + complete(&req->completion); +} + +int pcf50606_adc_sync_read(struct pcf50606 *pcf, int mux, int avg) +{ + + struct pcf50606_adc_request *req; + int result; + + /* req is freed when the result is ready, in pcf50606_work*/ + req = kzalloc(sizeof(*req), GFP_KERNEL); + if (!req) + return -ENOMEM; + + req->mux = mux; + req->avg = avg; + req->callback = pcf50606_adc_sync_read_callback; + req->callback_param = req; + init_completion(&req->completion); + + adc_enqueue_request(pcf, req); + + wait_for_completion(&req->completion); + result = req->result; + + return result; +} +EXPORT_SYMBOL_GPL(pcf50606_adc_sync_read); + +int pcf50606_adc_async_read(struct pcf50606 *pcf, int mux, int avg, + void (*callback)(struct pcf50606 *, void *, int), + void *callback_param) +{ + struct pcf50606_adc_request *req; + + /* req is freed when the result is ready, in pcf50606_work*/ + req = kmalloc(sizeof(*req), GFP_KERNEL); + if (!req) + return -ENOMEM; + + req->mux = mux; + req->avg = avg; + req->callback = callback; + req->callback_param = callback_param; + + adc_enqueue_request(pcf, req); + + return 0; +} +EXPORT_SYMBOL_GPL(pcf50606_adc_async_read); + +static int adc_result(struct pcf50606 *pcf) +{ + u16 ret = (pcf50606_reg_read(pcf, PCF50606_REG_ADCS1) << 2) | + (pcf50606_reg_read(pcf, PCF50606_REG_ADCS2) & 0x03); + + dev_info(pcf->dev, "adc result = %d\n", ret); + + return ret; +} + +static void pcf50606_adc_irq(struct pcf50606 *pcf, int irq, void *unused) +{ + struct pcf50606_adc_request *req; + int head; + + mutex_lock(&pcf->adc.queue_mutex); + head = pcf->adc.queue_head; + + req = pcf->adc.queue[head]; + if (!req) { + dev_err(pcf->dev, "ADC queue empty\n"); + mutex_unlock(&pcf->adc.queue_mutex); + return; + } + pcf->adc.queue[head] = NULL; + pcf->adc.queue_head = (head + 1) & + (PCF50606_MAX_ADC_FIFO_DEPTH - 1); + + mutex_unlock(&pcf->adc.queue_mutex); + req->callback(pcf, req->callback_param, adc_result(pcf)); + + kfree(req); + + trigger_next_adc_job_if_any(pcf); +} + +int __init pcf50606_adc_probe(struct platform_device *pdev) +{ + struct pcf50606 *pcf; + + pcf = platform_get_drvdata(pdev); + + /* Set up IRQ handlers */ + pcf->irq_handler[PCF50606_IRQ_ADCRDY].handler = pcf50606_adc_irq; + + mutex_init(&pcf->adc.queue_mutex); + return 0; +} + +static int __devexit pcf50606_adc_remove(struct platform_device *pdev) +{ + struct pcf50606 *pcf; + + pcf = platform_get_drvdata(pdev); + pcf->irq_handler[PCF50606_IRQ_ADCRDY].handler = NULL; + + return 0; +} + +struct platform_driver pcf50606_adc_driver = { + .driver = { + .name = "pcf50606-adc", + }, + .probe = pcf50606_adc_probe, + .remove = __devexit_p(pcf50606_adc_remove), +}; + +static int __init pcf50606_adc_init(void) +{ + return platform_driver_register(&pcf50606_adc_driver); +} +module_init(pcf50606_adc_init); + +static void __exit pcf50606_adc_exit(void) +{ + platform_driver_unregister(&pcf50606_adc_driver); +} +module_exit(pcf50606_adc_exit); + +MODULE_AUTHOR("Balaji Rao "); +MODULE_DESCRIPTION("PCF50606 adc driver"); +MODULE_LICENSE("GPL"); +MODULE_ALIAS("platform:pcf50606-adc"); + -- cgit v1.2.3