blob: 70fa18b04ad2bed52efa0be5e72dc416b637364a [file] [log] [blame]
// 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);
local_irq_disable();
service = isr & ~msr;
for (irq = pcap->irq_base; service; service >>= 1, irq++) {
if (service & 1)
generic_handle_irq(irq);
}
local_irq_enable();
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 int 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);
return 0;
}
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");