diff options
Diffstat (limited to 'drivers/mfd/ezx-pcap.c')
-rw-r--r-- | drivers/mfd/ezx-pcap.c | 541 |
1 files changed, 541 insertions, 0 deletions
diff --git a/drivers/mfd/ezx-pcap.c b/drivers/mfd/ezx-pcap.c new file mode 100644 index 000000000..5991faddd --- /dev/null +++ b/drivers/mfd/ezx-pcap.c @@ -0,0 +1,541 @@ +/* + * 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> + * + * This program is free software; you can redistribute it and/or modify + * it under the terms of the GNU General Public License version 2 as + * published by the Free Software Foundation. + * + */ + +#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; + struct mutex io_mutex; + + /* 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; + struct mutex adc_mutex; +}; + +/* 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) +{ + int ret; + + mutex_lock(&pcap->io_mutex); + value &= PCAP_REGISTER_VALUE_MASK; + value |= PCAP_REGISTER_WRITE_OP_BIT + | (reg_num << PCAP_REGISTER_ADDRESS_SHIFT); + ret = ezx_pcap_putget(pcap, &value); + mutex_unlock(&pcap->io_mutex); + + return ret; +} +EXPORT_SYMBOL_GPL(ezx_pcap_write); + +int ezx_pcap_read(struct pcap_chip *pcap, u8 reg_num, u32 *value) +{ + int ret; + + mutex_lock(&pcap->io_mutex); + *value = PCAP_REGISTER_READ_OP_BIT + | (reg_num << PCAP_REGISTER_ADDRESS_SHIFT); + + ret = ezx_pcap_putget(pcap, value); + mutex_unlock(&pcap->io_mutex); + + return ret; +} +EXPORT_SYMBOL_GPL(ezx_pcap_read); + +int ezx_pcap_set_bits(struct pcap_chip *pcap, u8 reg_num, u32 mask, u32 val) +{ + int ret; + u32 tmp = PCAP_REGISTER_READ_OP_BIT | + (reg_num << PCAP_REGISTER_ADDRESS_SHIFT); + + mutex_lock(&pcap->io_mutex); + 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: + mutex_unlock(&pcap->io_mutex); + + 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(unsigned int irq, struct irq_desc *desc) +{ + struct pcap_chip *pcap = irq_get_handler_data(irq); + + 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) +{ + u32 tmp; + + mutex_lock(&pcap->adc_mutex); + 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); + mutex_unlock(&pcap->adc_mutex); +} +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) +{ + u32 tmp; + u8 head; + + mutex_lock(&pcap->adc_mutex); + head = pcap->adc_head; + if (!pcap->adc_queue[head]) { + /* queue is empty, save power */ + pcap_disable_adc(pcap); + mutex_unlock(&pcap->adc_mutex); + 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); + mutex_unlock(&pcap->adc_mutex); + 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; + + mutex_lock(&pcap->adc_mutex); + req = pcap->adc_queue[pcap->adc_head]; + + if (WARN(!req, "adc irq without pending request\n")) { + mutex_unlock(&pcap->adc_mutex); + 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); + mutex_unlock(&pcap->adc_mutex); + + /* 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; + + /* 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; + + mutex_lock(&pcap->adc_mutex); + if (pcap->adc_queue[pcap->adc_tail]) { + mutex_unlock(&pcap->adc_mutex); + kfree(req); + return -EBUSY; + } + pcap->adc_queue[pcap->adc_tail] = req; + pcap->adc_tail = (pcap->adc_tail + 1) & (PCAP_ADC_MAXQ - 1); + mutex_unlock(&pcap->adc_mutex); + + /* 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); + int i; + + /* remove all registered subdevs */ + device_for_each_child(&spi->dev, NULL, pcap_remove_subdev); + + /* cleanup ADC */ + mutex_lock(&pcap->adc_mutex); + for (i = 0; i < PCAP_ADC_MAXQ; i++) + kfree(pcap->adc_queue[i]); + mutex_unlock(&pcap->adc_mutex); + + /* 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; + } + + mutex_init(&pcap->io_mutex); + mutex_init(&pcap->adc_mutex); + 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); +#ifdef CONFIG_ARM + set_irq_flags(i, IRQF_VALID); +#else + irq_set_noprobe(i); +#endif + } + + /* 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_handler_data(spi->irq, pcap); + irq_set_chained_handler(spi->irq, pcap_irq_handler); + 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", + .owner = THIS_MODULE, + }, +}; + +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"); |