From 9d1fd9e7b19d66a35ee4e760b30a3b9a168c20a2 Mon Sep 17 00:00:00 2001 From: Balaji Rao Date: Wed, 28 Jan 2009 19:30:42 +0000 Subject: Subject: pcf50606_rebase_changes,patch X-Git-Url: http://git.openmoko.org/?p=kernel.git;a=commitdiff_plain;h=938eddf17625cce0307f7612a3ea2560384e2384 pcf50606_rebase_changes,patch This patch brings into andy-tracking all changes related to pcf50606 from old balaji-tracking. --- drivers/mfd/pcf50606-adc.c | 279 +++++++++++++++++++++++++++++++++++++++++++++ 1 file changed, 279 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..fe0336b9753 --- /dev/null +++ b/drivers/mfd/pcf50606-adc.c @@ -0,0 +1,279 @@ +/* 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, Werner Almesberger and Matt Hsu + * + * 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. + * + * NOTE: This driver does not yet support subtractive ADC mode, which means + * you can do only one measurement per read request. + */ + +#include +#include +#include +#include +#include +#include + +#include +#include + +struct pcf50606_adc_request { + int mux; + int result; + void (*callback)(struct pcf50606 *, void *, int); + void *callback_param; + + /* Used in case of sync requests */ + struct completion completion; + +}; + +#define PCF50606_MAX_ADC_FIFO_DEPTH 8 + +struct pcf50606_adc { + struct pcf50606 *pcf; + + /* Private stuff */ + struct pcf50606_adc_request *queue[PCF50606_MAX_ADC_FIFO_DEPTH]; + int queue_head; + int queue_tail; + struct mutex queue_mutex; +}; + +static inline struct pcf50606_adc *__to_adc(struct pcf50606 *pcf) +{ + return platform_get_drvdata(pcf->adc_pdev); +} + +static void adc_setup(struct pcf50606 *pcf, int channel) +{ + 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) +{ + struct pcf50606_adc *adc = __to_adc(pcf); + int head, tail; + + mutex_lock(&adc->queue_mutex); + + head = adc->queue_head; + tail = adc->queue_tail; + + if (!adc->queue[head]) + goto out; + + adc_setup(pcf, adc->queue[head]->mux); +out: + mutex_unlock(&adc->queue_mutex); +} + +static int +adc_enqueue_request(struct pcf50606 *pcf, struct pcf50606_adc_request *req) +{ + struct pcf50606_adc *adc = __to_adc(pcf); + int head, tail; + + mutex_lock(&adc->queue_mutex); + head = adc->queue_head; + tail = adc->queue_tail; + + if (adc->queue[tail]) { + mutex_unlock(&adc->queue_mutex); + return -EBUSY; + } + + adc->queue[tail] = req; + + adc->queue_tail = + (tail + 1) & (PCF50606_MAX_ADC_FIFO_DEPTH - 1); + + mutex_unlock(&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) +{ + + struct pcf50606_adc_request *req; + int result; + + /* req is freed when the result is ready, in irq handler*/ + req = kzalloc(sizeof(*req), GFP_KERNEL); + if (!req) + return -ENOMEM; + + req->mux = mux; + req->callback = pcf50606_adc_sync_read_callback; + req->callback_param = req; + init_completion(&req->completion); + + adc_enqueue_request(pcf, req); + + if (wait_for_completion_timeout(&req->completion, 5 * HZ) == 5 * HZ) { + dev_err(pcf->dev, "ADC read timed out \n"); + } + + result = req->result; + + return result; +} +EXPORT_SYMBOL_GPL(pcf50606_adc_sync_read); + +int pcf50606_adc_async_read(struct pcf50606 *pcf, int mux, + 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->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(int irq, void *data) +{ + struct pcf50606_adc *adc = data; + struct pcf50606 *pcf = adc->pcf; + struct pcf50606_adc_request *req; + int head; + + mutex_lock(&adc->queue_mutex); + head = adc->queue_head; + + req = adc->queue[head]; + if (WARN_ON(!req)) { + dev_err(pcf->dev, "pcf50606-adc irq: ADC queue empty!\n"); + mutex_unlock(&adc->queue_mutex); + return; + } + + adc->queue[head] = NULL; + adc->queue_head = (head + 1) & + (PCF50606_MAX_ADC_FIFO_DEPTH - 1); + + mutex_unlock(&adc->queue_mutex); + + req->callback(pcf, req->callback_param, adc_result(pcf)); + kfree(req); + + trigger_next_adc_job_if_any(pcf); +} + +static int __devinit pcf50606_adc_probe(struct platform_device *pdev) +{ + struct pcf50606_subdev_pdata *pdata = pdev->dev.platform_data; + struct pcf50606_adc *adc; + + adc = kzalloc(sizeof(*adc), GFP_KERNEL); + if (!adc) + return -ENOMEM; + + adc->pcf = pdata->pcf; + platform_set_drvdata(pdev, adc); + + pcf50606_register_irq(pdata->pcf, PCF50606_IRQ_ADCRDY, + pcf50606_adc_irq, adc); + + mutex_init(&adc->queue_mutex); + + return 0; +} + +static int __devexit pcf50606_adc_remove(struct platform_device *pdev) +{ + struct pcf50606_adc *adc = platform_get_drvdata(pdev); + int i, head; + + pcf50606_free_irq(adc->pcf, PCF50606_IRQ_ADCRDY); + + mutex_lock(&adc->queue_mutex); + head = adc->queue_head; + + if (WARN_ON(adc->queue[head])) + dev_err(adc->pcf->dev, + "adc driver removed with request pending\n"); + + for (i = 0; i < PCF50606_MAX_ADC_FIFO_DEPTH; i++) + kfree(adc->queue[i]); + + mutex_unlock(&adc->queue_mutex); + kfree(adc); + + 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