1 files changed, 534 insertions, 0 deletions

diff --git a/drivers/mfd/ezx-pcap.c b/drivers/mfd/ezx-pcap.c
new file mode 100644
index 000000000..3d5ce18aa
--- /dev/null
+++ b/drivers/mfd/ezx-pcap.c
@@ -0,0 +1,534 @@
+// SPDX-License-Identifier: GPL-2.0-only
+/*
+ * Driver for Motorola PCAP2 as present in EZX phones
+ *
+ * Copyright (C) 2006 Harald Welte <laforge@openezx.org>
+ * Copyright (C) 2009 Daniel Ribeiro <drwyrm@gmail.com>
+ */
+
+#include <linux/module.h>
+#include <linux/kernel.h>
+#include <linux/platform_device.h>
+#include <linux/interrupt.h>
+#include <linux/irq.h>
+#include <linux/mfd/ezx-pcap.h>
+#include <linux/spi/spi.h>
+#include <linux/gpio.h>
+#include <linux/slab.h>
+
+#define PCAP_ADC_MAXQ		8
+struct pcap_adc_request {
+	u8 bank;
+	u8 ch[2];
+	u32 flags;
+	void (*callback)(void *, u16[]);
+	void *data;
+};
+
+struct pcap_adc_sync_request {
+	u16 res[2];
+	struct completion completion;
+};
+
+struct pcap_chip {
+	struct spi_device *spi;
+
+	/* IO */
+	u32 buf;
+	spinlock_t io_lock;
+
+	/* IRQ */
+	unsigned int irq_base;
+	u32 msr;
+	struct work_struct isr_work;
+	struct work_struct msr_work;
+	struct workqueue_struct *workqueue;
+
+	/* ADC */
+	struct pcap_adc_request *adc_queue[PCAP_ADC_MAXQ];
+	u8 adc_head;
+	u8 adc_tail;
+	spinlock_t adc_lock;
+};
+
+/* IO */
+static int ezx_pcap_putget(struct pcap_chip *pcap, u32 *data)
+{
+	struct spi_transfer t;
+	struct spi_message m;
+	int status;
+
+	memset(&t, 0, sizeof(t));
+	spi_message_init(&m);
+	t.len = sizeof(u32);
+	spi_message_add_tail(&t, &m);
+
+	pcap->buf = *data;
+	t.tx_buf = (u8 *) &pcap->buf;
+	t.rx_buf = (u8 *) &pcap->buf;
+	status = spi_sync(pcap->spi, &m);
+
+	if (status == 0)
+		*data = pcap->buf;
+
+	return status;
+}
+
+int ezx_pcap_write(struct pcap_chip *pcap, u8 reg_num, u32 value)
+{
+	unsigned long flags;
+	int ret;
+
+	spin_lock_irqsave(&pcap->io_lock, flags);
+	value &= PCAP_REGISTER_VALUE_MASK;
+	value |= PCAP_REGISTER_WRITE_OP_BIT
+		| (reg_num << PCAP_REGISTER_ADDRESS_SHIFT);
+	ret = ezx_pcap_putget(pcap, &value);
+	spin_unlock_irqrestore(&pcap->io_lock, flags);
+
+	return ret;
+}
+EXPORT_SYMBOL_GPL(ezx_pcap_write);
+
+int ezx_pcap_read(struct pcap_chip *pcap, u8 reg_num, u32 *value)
+{
+	unsigned long flags;
+	int ret;
+
+	spin_lock_irqsave(&pcap->io_lock, flags);
+	*value = PCAP_REGISTER_READ_OP_BIT
+		| (reg_num << PCAP_REGISTER_ADDRESS_SHIFT);
+
+	ret = ezx_pcap_putget(pcap, value);
+	spin_unlock_irqrestore(&pcap->io_lock, flags);
+
+	return ret;
+}
+EXPORT_SYMBOL_GPL(ezx_pcap_read);
+
+int ezx_pcap_set_bits(struct pcap_chip *pcap, u8 reg_num, u32 mask, u32 val)
+{
+	unsigned long flags;
+	int ret;
+	u32 tmp = PCAP_REGISTER_READ_OP_BIT |
+		(reg_num << PCAP_REGISTER_ADDRESS_SHIFT);
+
+	spin_lock_irqsave(&pcap->io_lock, flags);
+	ret = ezx_pcap_putget(pcap, &tmp);
+	if (ret)
+		goto out_unlock;
+
+	tmp &= (PCAP_REGISTER_VALUE_MASK & ~mask);
+	tmp |= (val & mask) | PCAP_REGISTER_WRITE_OP_BIT |
+		(reg_num << PCAP_REGISTER_ADDRESS_SHIFT);
+
+	ret = ezx_pcap_putget(pcap, &tmp);
+out_unlock:
+	spin_unlock_irqrestore(&pcap->io_lock, flags);
+
+	return ret;
+}
+EXPORT_SYMBOL_GPL(ezx_pcap_set_bits);
+
+/* IRQ */
+int irq_to_pcap(struct pcap_chip *pcap, int irq)
+{
+	return irq - pcap->irq_base;
+}
+EXPORT_SYMBOL_GPL(irq_to_pcap);
+
+int pcap_to_irq(struct pcap_chip *pcap, int irq)
+{
+	return pcap->irq_base + irq;
+}
+EXPORT_SYMBOL_GPL(pcap_to_irq);
+
+static void pcap_mask_irq(struct irq_data *d)
+{
+	struct pcap_chip *pcap = irq_data_get_irq_chip_data(d);
+
+	pcap->msr |= 1 << irq_to_pcap(pcap, d->irq);
+	queue_work(pcap->workqueue, &pcap->msr_work);
+}
+
+static void pcap_unmask_irq(struct irq_data *d)
+{
+	struct pcap_chip *pcap = irq_data_get_irq_chip_data(d);
+
+	pcap->msr &= ~(1 << irq_to_pcap(pcap, d->irq));
+	queue_work(pcap->workqueue, &pcap->msr_work);
+}
+
+static struct irq_chip pcap_irq_chip = {
+	.name		= "pcap",
+	.irq_disable	= pcap_mask_irq,
+	.irq_mask	= pcap_mask_irq,
+	.irq_unmask	= pcap_unmask_irq,
+};
+
+static void pcap_msr_work(struct work_struct *work)
+{
+	struct pcap_chip *pcap = container_of(work, struct pcap_chip, msr_work);
+
+	ezx_pcap_write(pcap, PCAP_REG_MSR, pcap->msr);
+}
+
+static void pcap_isr_work(struct work_struct *work)
+{
+	struct pcap_chip *pcap = container_of(work, struct pcap_chip, isr_work);
+	struct pcap_platform_data *pdata = dev_get_platdata(&pcap->spi->dev);
+	u32 msr, isr, int_sel, service;
+	int irq;
+
+	do {
+		ezx_pcap_read(pcap, PCAP_REG_MSR, &msr);
+		ezx_pcap_read(pcap, PCAP_REG_ISR, &isr);
+
+		/* We can't service/ack irqs that are assigned to port 2 */
+		if (!(pdata->config & PCAP_SECOND_PORT)) {
+			ezx_pcap_read(pcap, PCAP_REG_INT_SEL, &int_sel);
+			isr &= ~int_sel;
+		}
+
+		ezx_pcap_write(pcap, PCAP_REG_MSR, isr | msr);
+		ezx_pcap_write(pcap, PCAP_REG_ISR, isr);
+
+		service = isr & ~msr;
+		for (irq = pcap->irq_base; service; service >>= 1, irq++) {
+			if (service & 1)
+				generic_handle_irq_safe(irq);
+		}
+		ezx_pcap_write(pcap, PCAP_REG_MSR, pcap->msr);
+	} while (gpio_get_value(pdata->gpio));
+}
+
+static void pcap_irq_handler(struct irq_desc *desc)
+{
+	struct pcap_chip *pcap = irq_desc_get_handler_data(desc);
+
+	desc->irq_data.chip->irq_ack(&desc->irq_data);
+	queue_work(pcap->workqueue, &pcap->isr_work);
+}
+
+/* ADC */
+void pcap_set_ts_bits(struct pcap_chip *pcap, u32 bits)
+{
+	unsigned long flags;
+	u32 tmp;
+
+	spin_lock_irqsave(&pcap->adc_lock, flags);
+	ezx_pcap_read(pcap, PCAP_REG_ADC, &tmp);
+	tmp &= ~(PCAP_ADC_TS_M_MASK | PCAP_ADC_TS_REF_LOWPWR);
+	tmp |= bits & (PCAP_ADC_TS_M_MASK | PCAP_ADC_TS_REF_LOWPWR);
+	ezx_pcap_write(pcap, PCAP_REG_ADC, tmp);
+	spin_unlock_irqrestore(&pcap->adc_lock, flags);
+}
+EXPORT_SYMBOL_GPL(pcap_set_ts_bits);
+
+static void pcap_disable_adc(struct pcap_chip *pcap)
+{
+	u32 tmp;
+
+	ezx_pcap_read(pcap, PCAP_REG_ADC, &tmp);
+	tmp &= ~(PCAP_ADC_ADEN|PCAP_ADC_BATT_I_ADC|PCAP_ADC_BATT_I_POLARITY);
+	ezx_pcap_write(pcap, PCAP_REG_ADC, tmp);
+}
+
+static void pcap_adc_trigger(struct pcap_chip *pcap)
+{
+	unsigned long flags;
+	u32 tmp;
+	u8 head;
+
+	spin_lock_irqsave(&pcap->adc_lock, flags);
+	head = pcap->adc_head;
+	if (!pcap->adc_queue[head]) {
+		/* queue is empty, save power */
+		pcap_disable_adc(pcap);
+		spin_unlock_irqrestore(&pcap->adc_lock, flags);
+		return;
+	}
+	/* start conversion on requested bank, save TS_M bits */
+	ezx_pcap_read(pcap, PCAP_REG_ADC, &tmp);
+	tmp &= (PCAP_ADC_TS_M_MASK | PCAP_ADC_TS_REF_LOWPWR);
+	tmp |= pcap->adc_queue[head]->flags | PCAP_ADC_ADEN;
+
+	if (pcap->adc_queue[head]->bank == PCAP_ADC_BANK_1)
+		tmp |= PCAP_ADC_AD_SEL1;
+
+	ezx_pcap_write(pcap, PCAP_REG_ADC, tmp);
+	spin_unlock_irqrestore(&pcap->adc_lock, flags);
+	ezx_pcap_write(pcap, PCAP_REG_ADR, PCAP_ADR_ASC);
+}
+
+static irqreturn_t pcap_adc_irq(int irq, void *_pcap)
+{
+	struct pcap_chip *pcap = _pcap;
+	struct pcap_adc_request *req;
+	u16 res[2];
+	u32 tmp;
+
+	spin_lock(&pcap->adc_lock);
+	req = pcap->adc_queue[pcap->adc_head];
+
+	if (WARN(!req, "adc irq without pending request\n")) {
+		spin_unlock(&pcap->adc_lock);
+		return IRQ_HANDLED;
+	}
+
+	/* read requested channels results */
+	ezx_pcap_read(pcap, PCAP_REG_ADC, &tmp);
+	tmp &= ~(PCAP_ADC_ADA1_MASK | PCAP_ADC_ADA2_MASK);
+	tmp |= (req->ch[0] << PCAP_ADC_ADA1_SHIFT);
+	tmp |= (req->ch[1] << PCAP_ADC_ADA2_SHIFT);
+	ezx_pcap_write(pcap, PCAP_REG_ADC, tmp);
+	ezx_pcap_read(pcap, PCAP_REG_ADR, &tmp);
+	res[0] = (tmp & PCAP_ADR_ADD1_MASK) >> PCAP_ADR_ADD1_SHIFT;
+	res[1] = (tmp & PCAP_ADR_ADD2_MASK) >> PCAP_ADR_ADD2_SHIFT;
+
+	pcap->adc_queue[pcap->adc_head] = NULL;
+	pcap->adc_head = (pcap->adc_head + 1) & (PCAP_ADC_MAXQ - 1);
+	spin_unlock(&pcap->adc_lock);
+
+	/* pass the results and release memory */
+	req->callback(req->data, res);
+	kfree(req);
+
+	/* trigger next conversion (if any) on queue */
+	pcap_adc_trigger(pcap);
+
+	return IRQ_HANDLED;
+}
+
+int pcap_adc_async(struct pcap_chip *pcap, u8 bank, u32 flags, u8 ch[],
+						void *callback, void *data)
+{
+	struct pcap_adc_request *req;
+	unsigned long irq_flags;
+
+	/* This will be freed after we have a result */
+	req = kmalloc(sizeof(struct pcap_adc_request), GFP_KERNEL);
+	if (!req)
+		return -ENOMEM;
+
+	req->bank = bank;
+	req->flags = flags;
+	req->ch[0] = ch[0];
+	req->ch[1] = ch[1];
+	req->callback = callback;
+	req->data = data;
+
+	spin_lock_irqsave(&pcap->adc_lock, irq_flags);
+	if (pcap->adc_queue[pcap->adc_tail]) {
+		spin_unlock_irqrestore(&pcap->adc_lock, irq_flags);
+		kfree(req);
+		return -EBUSY;
+	}
+	pcap->adc_queue[pcap->adc_tail] = req;
+	pcap->adc_tail = (pcap->adc_tail + 1) & (PCAP_ADC_MAXQ - 1);
+	spin_unlock_irqrestore(&pcap->adc_lock, irq_flags);
+
+	/* start conversion */
+	pcap_adc_trigger(pcap);
+
+	return 0;
+}
+EXPORT_SYMBOL_GPL(pcap_adc_async);
+
+static void pcap_adc_sync_cb(void *param, u16 res[])
+{
+	struct pcap_adc_sync_request *req = param;
+
+	req->res[0] = res[0];
+	req->res[1] = res[1];
+	complete(&req->completion);
+}
+
+int pcap_adc_sync(struct pcap_chip *pcap, u8 bank, u32 flags, u8 ch[],
+								u16 res[])
+{
+	struct pcap_adc_sync_request sync_data;
+	int ret;
+
+	init_completion(&sync_data.completion);
+	ret = pcap_adc_async(pcap, bank, flags, ch, pcap_adc_sync_cb,
+								&sync_data);
+	if (ret)
+		return ret;
+	wait_for_completion(&sync_data.completion);
+	res[0] = sync_data.res[0];
+	res[1] = sync_data.res[1];
+
+	return 0;
+}
+EXPORT_SYMBOL_GPL(pcap_adc_sync);
+
+/* subdevs */
+static int pcap_remove_subdev(struct device *dev, void *unused)
+{
+	platform_device_unregister(to_platform_device(dev));
+	return 0;
+}
+
+static int pcap_add_subdev(struct pcap_chip *pcap,
+						struct pcap_subdev *subdev)
+{
+	struct platform_device *pdev;
+	int ret;
+
+	pdev = platform_device_alloc(subdev->name, subdev->id);
+	if (!pdev)
+		return -ENOMEM;
+
+	pdev->dev.parent = &pcap->spi->dev;
+	pdev->dev.platform_data = subdev->platform_data;
+
+	ret = platform_device_add(pdev);
+	if (ret)
+		platform_device_put(pdev);
+
+	return ret;
+}
+
+static void ezx_pcap_remove(struct spi_device *spi)
+{
+	struct pcap_chip *pcap = spi_get_drvdata(spi);
+	unsigned long flags;
+	int i;
+
+	/* remove all registered subdevs */
+	device_for_each_child(&spi->dev, NULL, pcap_remove_subdev);
+
+	/* cleanup ADC */
+	spin_lock_irqsave(&pcap->adc_lock, flags);
+	for (i = 0; i < PCAP_ADC_MAXQ; i++)
+		kfree(pcap->adc_queue[i]);
+	spin_unlock_irqrestore(&pcap->adc_lock, flags);
+
+	/* cleanup irqchip */
+	for (i = pcap->irq_base; i < (pcap->irq_base + PCAP_NIRQS); i++)
+		irq_set_chip_and_handler(i, NULL, NULL);
+
+	destroy_workqueue(pcap->workqueue);
+}
+
+static int ezx_pcap_probe(struct spi_device *spi)
+{
+	struct pcap_platform_data *pdata = dev_get_platdata(&spi->dev);
+	struct pcap_chip *pcap;
+	int i, adc_irq;
+	int ret = -ENODEV;
+
+	/* platform data is required */
+	if (!pdata)
+		goto ret;
+
+	pcap = devm_kzalloc(&spi->dev, sizeof(*pcap), GFP_KERNEL);
+	if (!pcap) {
+		ret = -ENOMEM;
+		goto ret;
+	}
+
+	spin_lock_init(&pcap->io_lock);
+	spin_lock_init(&pcap->adc_lock);
+	INIT_WORK(&pcap->isr_work, pcap_isr_work);
+	INIT_WORK(&pcap->msr_work, pcap_msr_work);
+	spi_set_drvdata(spi, pcap);
+
+	/* setup spi */
+	spi->bits_per_word = 32;
+	spi->mode = SPI_MODE_0 | (pdata->config & PCAP_CS_AH ? SPI_CS_HIGH : 0);
+	ret = spi_setup(spi);
+	if (ret)
+		goto ret;
+
+	pcap->spi = spi;
+
+	/* setup irq */
+	pcap->irq_base = pdata->irq_base;
+	pcap->workqueue = create_singlethread_workqueue("pcapd");
+	if (!pcap->workqueue) {
+		ret = -ENOMEM;
+		dev_err(&spi->dev, "can't create pcap thread\n");
+		goto ret;
+	}
+
+	/* redirect interrupts to AP, except adcdone2 */
+	if (!(pdata->config & PCAP_SECOND_PORT))
+		ezx_pcap_write(pcap, PCAP_REG_INT_SEL,
+					(1 << PCAP_IRQ_ADCDONE2));
+
+	/* setup irq chip */
+	for (i = pcap->irq_base; i < (pcap->irq_base + PCAP_NIRQS); i++) {
+		irq_set_chip_and_handler(i, &pcap_irq_chip, handle_simple_irq);
+		irq_set_chip_data(i, pcap);
+		irq_clear_status_flags(i, IRQ_NOREQUEST | IRQ_NOPROBE);
+	}
+
+	/* mask/ack all PCAP interrupts */
+	ezx_pcap_write(pcap, PCAP_REG_MSR, PCAP_MASK_ALL_INTERRUPT);
+	ezx_pcap_write(pcap, PCAP_REG_ISR, PCAP_CLEAR_INTERRUPT_REGISTER);
+	pcap->msr = PCAP_MASK_ALL_INTERRUPT;
+
+	irq_set_irq_type(spi->irq, IRQ_TYPE_EDGE_RISING);
+	irq_set_chained_handler_and_data(spi->irq, pcap_irq_handler, pcap);
+	irq_set_irq_wake(spi->irq, 1);
+
+	/* ADC */
+	adc_irq = pcap_to_irq(pcap, (pdata->config & PCAP_SECOND_PORT) ?
+					PCAP_IRQ_ADCDONE2 : PCAP_IRQ_ADCDONE);
+
+	ret = devm_request_irq(&spi->dev, adc_irq, pcap_adc_irq, 0, "ADC",
+				pcap);
+	if (ret)
+		goto free_irqchip;
+
+	/* setup subdevs */
+	for (i = 0; i < pdata->num_subdevs; i++) {
+		ret = pcap_add_subdev(pcap, &pdata->subdevs[i]);
+		if (ret)
+			goto remove_subdevs;
+	}
+
+	/* board specific quirks */
+	if (pdata->init)
+		pdata->init(pcap);
+
+	return 0;
+
+remove_subdevs:
+	device_for_each_child(&spi->dev, NULL, pcap_remove_subdev);
+free_irqchip:
+	for (i = pcap->irq_base; i < (pcap->irq_base + PCAP_NIRQS); i++)
+		irq_set_chip_and_handler(i, NULL, NULL);
+/* destroy_workqueue: */
+	destroy_workqueue(pcap->workqueue);
+ret:
+	return ret;
+}
+
+static struct spi_driver ezxpcap_driver = {
+	.probe	= ezx_pcap_probe,
+	.remove = ezx_pcap_remove,
+	.driver = {
+		.name	= "ezx-pcap",
+	},
+};
+
+static int __init ezx_pcap_init(void)
+{
+	return spi_register_driver(&ezxpcap_driver);
+}
+
+static void __exit ezx_pcap_exit(void)
+{
+	spi_unregister_driver(&ezxpcap_driver);
+}
+
+subsys_initcall(ezx_pcap_init);
+module_exit(ezx_pcap_exit);
+
+MODULE_LICENSE("GPL");
+MODULE_AUTHOR("Daniel Ribeiro / Harald Welte");
+MODULE_DESCRIPTION("Motorola PCAP2 ASIC Driver");
+MODULE_ALIAS("spi:ezx-pcap");