From 5557b3223d35dd25366d6ef047299b1dc94b17e6 Mon Sep 17 00:00:00 2001 From: Balaji Rao Date: Thu, 20 Nov 2008 19:46:51 +0000 Subject: pcf50633_mfd.patch pcf50633 driver rewritten to use the MFD model. --- drivers/mfd/pcf50633-adc.c | 218 +++++++++++++++++++++++++++++++++++++++++++++ 1 file changed, 218 insertions(+) create mode 100644 drivers/mfd/pcf50633-adc.c (limited to 'drivers/mfd/pcf50633-adc.c') diff --git a/drivers/mfd/pcf50633-adc.c b/drivers/mfd/pcf50633-adc.c new file mode 100644 index 00000000000..208c1f87e5d --- /dev/null +++ b/drivers/mfd/pcf50633-adc.c @@ -0,0 +1,218 @@ +#include +#include + +struct pcf50633_adc_request { + int mux; + int avg; + int result; + void (*callback)(struct pcf50633 *, void *, int); + void *callback_param; + + /* Used in case of sync requests */ + struct completion completion; + +}; + +static void adc_read_setup(struct pcf50633 *pcf, + int channel, int avg) +{ + channel &= PCF50633_ADCC1_ADCMUX_MASK; + + /* kill ratiometric, but enable ACCSW biasing */ + pcf50633_reg_write(pcf, PCF50633_REG_ADCC2, 0x00); + pcf50633_reg_write(pcf, PCF50633_REG_ADCC3, 0x01); + + /* start ADC conversion of selected channel */ + pcf50633_reg_write(pcf, PCF50633_REG_ADCC1, channel | avg | + PCF50633_ADCC1_ADCSTART | PCF50633_ADCC1_RES_10BIT); + +} + +static void trigger_next_adc_job_if_any(struct pcf50633 *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 pcf50633 *pcf, struct pcf50633_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) & (PCF50633_MAX_ADC_FIFO_DEPTH - 1); + + mutex_unlock(&pcf->adc.queue_mutex); + + trigger_next_adc_job_if_any(pcf); + + return 0; +} + +static void +pcf50633_adc_sync_read_callback(struct pcf50633 *pcf, void *param, int result) +{ + struct pcf50633_adc_request *req; + + /*We know here that the passed param is an adc_request object */ + req = (struct pcf50633_adc_request *)param; + + req->result = result; + complete(&req->completion); +} + +int pcf50633_adc_sync_read(struct pcf50633 *pcf, int mux, int avg) +{ + + struct pcf50633_adc_request *req; + int result; + + /* req is freed when the result is ready, in pcf50633_work*/ + req = kzalloc(sizeof(*req), GFP_KERNEL); + if (!req) + return -ENOMEM; + + req->mux = mux; + req->avg = avg; + req->callback = pcf50633_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(pcf50633_adc_sync_read); + +int pcf50633_adc_async_read(struct pcf50633 *pcf, int mux, int avg, + void (*callback)(struct pcf50633 *, void *, int), + void *callback_param) +{ + struct pcf50633_adc_request *req; + + /* req is freed when the result is ready, in pcf50633_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(pcf50633_adc_async_read); + +static int adc_result(struct pcf50633 *pcf) +{ + u16 ret = (pcf50633_reg_read(pcf, PCF50633_REG_ADCS1) << 2) | + (pcf50633_reg_read(pcf, PCF50633_REG_ADCS3) & + PCF50633_ADCS3_ADCDAT1L_MASK); + dev_info(pcf->dev, "adc result = %d\n", ret); + + return ret; +} + +static void pcf50633_adc_irq(struct pcf50633 *pcf, int irq, void *unused) +{ + struct pcf50633_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) & + (PCF50633_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 pcf50633_adc_probe(struct platform_device *pdev) +{ + struct pcf50633 *pcf; + + pcf = platform_get_drvdata(pdev); + + /* Set up IRQ handlers */ + pcf->irq_handler[PCF50633_IRQ_ADCRDY].handler = pcf50633_adc_irq; + + mutex_init(&pcf->adc.queue_mutex); + return 0; +} + +static int __devexit pcf50633_adc_remove(struct platform_device *pdev) +{ + struct pcf50633 *pcf; + + pcf = platform_get_drvdata(pdev); + pcf->irq_handler[PCF50633_IRQ_ADCRDY].handler = NULL; + + return 0; +} + +struct platform_driver pcf50633_adc_driver = { + .driver = { + .name = "pcf50633-adc", + }, + .probe = pcf50633_adc_probe, + .remove = __devexit_p(pcf50633_adc_remove), +}; + +static int __init pcf50633_adc_init(void) +{ + return platform_driver_register(&pcf50633_adc_driver); +} +module_init(pcf50633_adc_init); + +static void __exit pcf50633_adc_exit(void) +{ + platform_driver_unregister(&pcf50633_adc_driver); +} +module_exit(pcf50633_adc_exit); + +MODULE_AUTHOR("Balaji Rao "); +MODULE_DESCRIPTION("PCF50633 adc driver"); +MODULE_LICENSE("GPL"); +MODULE_ALIAS("platform:pcf50633-adc"); + -- cgit v1.2.3