diff options
Diffstat (limited to 'drivers/mfd/pcf50633-adc.c')
| -rw-r--r-- | drivers/mfd/pcf50633-adc.c | 177 |
1 files changed, 101 insertions, 76 deletions
diff --git a/drivers/mfd/pcf50633-adc.c b/drivers/mfd/pcf50633-adc.c index e3d4eb1c03f..c2d05becfa9 100644 --- a/drivers/mfd/pcf50633-adc.c +++ b/drivers/mfd/pcf50633-adc.c @@ -1,4 +1,4 @@ -/* Philips PCF50633 ADC Driver +/* NXP PCF50633 ADC Driver * * (C) 2006-2008 by Openmoko, Inc. * Author: Balaji Rao <balajirrao@openmoko.org> @@ -7,26 +7,21 @@ * Broken down from monstrous PCF50633 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 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 + * NOTE: This driver does not yet support subtractive ADC mode, which means + * you can do only one measurement per read request. */ -/* - * NOTE: This driver does not yet support subtractive ADC mode, which means - * you can do only one measurement per read request. - */ +#include <linux/kernel.h> +#include <linux/module.h> +#include <linux/init.h> +#include <linux/device.h> +#include <linux/platform_device.h> +#include <linux/completion.h> #include <linux/mfd/pcf50633/core.h> #include <linux/mfd/pcf50633/adc.h> @@ -43,8 +38,24 @@ struct pcf50633_adc_request { }; -static void adc_read_setup(struct pcf50633 *pcf, - int channel, int avg) +#define PCF50633_MAX_ADC_FIFO_DEPTH 8 + +struct pcf50633_adc { + struct pcf50633 *pcf; + + /* Private stuff */ + struct pcf50633_adc_request *queue[PCF50633_MAX_ADC_FIFO_DEPTH]; + int queue_head; + int queue_tail; + struct mutex queue_mutex; +}; + +static inline struct pcf50633_adc *__to_adc(struct pcf50633 *pcf) +{ + return platform_get_drvdata(pcf->adc_pdev); +} + +static void adc_setup(struct pcf50633 *pcf, int channel, int avg) { channel &= PCF50633_ADCC1_ADCMUX_MASK; @@ -55,47 +66,46 @@ static void adc_read_setup(struct pcf50633 *pcf, /* start ADC conversion on 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; + struct pcf50633_adc *adc = __to_adc(pcf); + int head; - mutex_lock(&pcf->adc.queue_mutex); + mutex_lock(&adc->queue_mutex); - head = pcf->adc.queue_head; - tail = pcf->adc.queue_tail; + head = adc->queue_head; - if (!pcf->adc.queue[head]) - goto out; + if (!adc->queue[head]) { + mutex_unlock(&adc->queue_mutex); + return; + } + mutex_unlock(&adc->queue_mutex); - adc_read_setup(pcf, pcf->adc.queue[head]->mux, - pcf->adc.queue[head]->avg); -out: - mutex_unlock(&pcf->adc.queue_mutex); + adc_setup(pcf, adc->queue[head]->mux, adc->queue[head]->avg); } static int adc_enqueue_request(struct pcf50633 *pcf, struct pcf50633_adc_request *req) { + struct pcf50633_adc *adc = __to_adc(pcf); int head, tail; - mutex_lock(&pcf->adc.queue_mutex); - head = pcf->adc.queue_head; - tail = pcf->adc.queue_tail; + mutex_lock(&adc->queue_mutex); - if (pcf->adc.queue[tail]) { - mutex_unlock(&pcf->adc.queue_mutex); + head = adc->queue_head; + tail = adc->queue_tail; + + if (adc->queue[tail]) { + mutex_unlock(&adc->queue_mutex); return -EBUSY; } - pcf->adc.queue[tail] = req; - - pcf->adc.queue_tail = - (tail + 1) & (PCF50633_MAX_ADC_FIFO_DEPTH - 1); + adc->queue[tail] = req; + adc->queue_tail = (tail + 1) & (PCF50633_MAX_ADC_FIFO_DEPTH - 1); - mutex_unlock(&pcf->adc.queue_mutex); + mutex_unlock(&adc->queue_mutex); trigger_next_adc_job_if_any(pcf); @@ -105,10 +115,7 @@ adc_enqueue_request(struct pcf50633 *pcf, struct pcf50633_adc_request *req) 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; + struct pcf50633_adc_request *req = param; req->result = result; complete(&req->completion); @@ -116,9 +123,7 @@ pcf50633_adc_sync_read_callback(struct pcf50633 *pcf, void *param, int result) 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 interrupt handler */ req = kzalloc(sizeof(*req), GFP_KERNEL); @@ -129,14 +134,12 @@ int pcf50633_adc_sync_read(struct pcf50633 *pcf, int mux, int avg) req->avg = avg; req->callback = pcf50633_adc_sync_read_callback; req->callback_param = req; - init_completion(&req->completion); + init_completion(&req->completion); adc_enqueue_request(pcf, req); - wait_for_completion(&req->completion); - result = req->result; - return result; + return req->result; } EXPORT_SYMBOL_GPL(pcf50633_adc_sync_read); @@ -166,66 +169,88 @@ static int adc_result(struct pcf50633 *pcf) { u8 adcs1, adcs3; u16 result; - + adcs1 = pcf50633_reg_read(pcf, PCF50633_REG_ADCS1); adcs3 = pcf50633_reg_read(pcf, PCF50633_REG_ADCS3); result = (adcs1 << 2) | (adcs3 & PCF50633_ADCS3_ADCDAT1L_MASK); - dev_info(pcf->dev, "adc result = %d\n", result); + dev_dbg(pcf->dev, "adc result = %d\n", result); return result; } -static void pcf50633_adc_irq(struct pcf50633 *pcf, int irq, void *unused) +static void pcf50633_adc_irq(int irq, void *data) { + struct pcf50633_adc *adc = data; + struct pcf50633 *pcf = adc->pcf; struct pcf50633_adc_request *req; int head; - mutex_lock(&pcf->adc.queue_mutex); - head = pcf->adc.queue_head; + mutex_lock(&adc->queue_mutex); + head = adc->queue_head; - req = pcf->adc.queue[head]; - if (!req) { - dev_err(pcf->dev, "ADC queue empty\n"); - mutex_unlock(&pcf->adc.queue_mutex); + req = adc->queue[head]; + if (WARN_ON(!req)) { + dev_err(pcf->dev, "pcf50633-adc irq: ADC queue empty!\n"); + mutex_unlock(&adc->queue_mutex); return; } - pcf->adc.queue[head] = NULL; - pcf->adc.queue_head = (head + 1) & + adc->queue[head] = NULL; + 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)); + mutex_unlock(&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) +static int __devinit pcf50633_adc_probe(struct platform_device *pdev) { - struct pcf50633 *pcf; + struct pcf50633_subdev_pdata *pdata = pdev->dev.platform_data; + struct pcf50633_adc *adc; + + adc = kzalloc(sizeof(*adc), GFP_KERNEL); + if (!adc) + return -ENOMEM; - pcf = platform_get_drvdata(pdev); + adc->pcf = pdata->pcf; + platform_set_drvdata(pdev, adc); - /* Set up IRQ handlers */ - pcf->irq_handler[PCF50633_IRQ_ADCRDY].handler = pcf50633_adc_irq; + pcf50633_register_irq(pdata->pcf, PCF50633_IRQ_ADCRDY, + pcf50633_adc_irq, adc); + + mutex_init(&adc->queue_mutex); - mutex_init(&pcf->adc.queue_mutex); return 0; } static int __devexit pcf50633_adc_remove(struct platform_device *pdev) { - struct pcf50633 *pcf; + struct pcf50633_adc *adc = platform_get_drvdata(pdev); + int i, head; + + pcf50633_free_irq(adc->pcf, PCF50633_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 < PCF50633_MAX_ADC_FIFO_DEPTH; i++) + kfree(adc->queue[i]); - pcf = platform_get_drvdata(pdev); - pcf->irq_handler[PCF50633_IRQ_ADCRDY].handler = NULL; + mutex_unlock(&adc->queue_mutex); + kfree(adc); return 0; } -struct platform_driver pcf50633_adc_driver = { +static struct platform_driver pcf50633_adc_driver = { .driver = { .name = "pcf50633-adc", }, @@ -235,13 +260,13 @@ struct platform_driver pcf50633_adc_driver = { static int __init pcf50633_adc_init(void) { - return platform_driver_register(&pcf50633_adc_driver); + 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); + platform_driver_unregister(&pcf50633_adc_driver); } module_exit(pcf50633_adc_exit); |