pcf50633_mfd.patch

pcf50633 driver rewritten to use the MFD model.

1 files changed, 218 insertions, 0 deletions

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 <linux/mfd/pcf50633/core.h>
+#include <linux/mfd/pcf50633/adc.h>
+
+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 <balajirrao@openmoko.org>");
+MODULE_DESCRIPTION("PCF50633 adc driver");
+MODULE_LICENSE("GPL");
+MODULE_ALIAS("platform:pcf50633-adc");
+