From 91f4debf5e2df904e7fade530bd1a6d182efd72c Mon Sep 17 00:00:00 2001 From: Lars-Peter Clausen Date: Mon, 12 Jul 2010 03:48:08 +0200 Subject: mfd: Add JZ4740 ADC driver This patch adds a MFD driver for the JZ4740 ADC unit. The driver is used to demultiplex IRQs and synchronize access to shared registers between the battery, hwmon and (future) touchscreen driver. Signed-off-by: Lars-Peter Clausen Signed-off-by: Samuel Ortiz --- drivers/mfd/jz4740-adc.c | 384 +++++++++++++++++++++++++++++++++++++++++++++++ 1 file changed, 384 insertions(+) create mode 100644 drivers/mfd/jz4740-adc.c (limited to 'drivers/mfd/jz4740-adc.c') diff --git a/drivers/mfd/jz4740-adc.c b/drivers/mfd/jz4740-adc.c new file mode 100644 index 00000000000..7a844aef5dc --- /dev/null +++ b/drivers/mfd/jz4740-adc.c @@ -0,0 +1,384 @@ +/* + * Copyright (C) 2009-2010, Lars-Peter Clausen + * JZ4740 SoC ADC driver + * + * 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. + * + * 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., + * 675 Mass Ave, Cambridge, MA 02139, USA. + * + * This driver synchronizes access to the JZ4740 ADC core between the + * JZ4740 battery and hwmon drivers. + */ + +#include +#include +#include +#include +#include +#include +#include +#include + +#include +#include + +#include + + +#define JZ_REG_ADC_ENABLE 0x00 +#define JZ_REG_ADC_CFG 0x04 +#define JZ_REG_ADC_CTRL 0x08 +#define JZ_REG_ADC_STATUS 0x0c + +#define JZ_REG_ADC_TOUCHSCREEN_BASE 0x10 +#define JZ_REG_ADC_BATTERY_BASE 0x1c +#define JZ_REG_ADC_HWMON_BASE 0x20 + +#define JZ_ADC_ENABLE_TOUCH BIT(2) +#define JZ_ADC_ENABLE_BATTERY BIT(1) +#define JZ_ADC_ENABLE_ADCIN BIT(0) + +enum { + JZ_ADC_IRQ_ADCIN = 0, + JZ_ADC_IRQ_BATTERY, + JZ_ADC_IRQ_TOUCH, + JZ_ADC_IRQ_PENUP, + JZ_ADC_IRQ_PENDOWN, +}; + +struct jz4740_adc { + struct resource *mem; + void __iomem *base; + + int irq; + int irq_base; + + struct clk *clk; + atomic_t clk_ref; + + spinlock_t lock; +}; + +static inline void jz4740_adc_irq_set_masked(struct jz4740_adc *adc, int irq, + bool masked) +{ + unsigned long flags; + uint8_t val; + + irq -= adc->irq_base; + + spin_lock_irqsave(&adc->lock, flags); + + val = readb(adc->base + JZ_REG_ADC_CTRL); + if (masked) + val |= BIT(irq); + else + val &= ~BIT(irq); + writeb(val, adc->base + JZ_REG_ADC_CTRL); + + spin_unlock_irqrestore(&adc->lock, flags); +} + +static void jz4740_adc_irq_mask(unsigned int irq) +{ + struct jz4740_adc *adc = get_irq_chip_data(irq); + jz4740_adc_irq_set_masked(adc, irq, true); +} + +static void jz4740_adc_irq_unmask(unsigned int irq) +{ + struct jz4740_adc *adc = get_irq_chip_data(irq); + jz4740_adc_irq_set_masked(adc, irq, false); +} + +static void jz4740_adc_irq_ack(unsigned int irq) +{ + struct jz4740_adc *adc = get_irq_chip_data(irq); + + irq -= adc->irq_base; + writeb(BIT(irq), adc->base + JZ_REG_ADC_STATUS); +} + +static struct irq_chip jz4740_adc_irq_chip = { + .name = "jz4740-adc", + .mask = jz4740_adc_irq_mask, + .unmask = jz4740_adc_irq_unmask, + .ack = jz4740_adc_irq_ack, +}; + +static void jz4740_adc_irq_demux(unsigned int irq, struct irq_desc *desc) +{ + struct jz4740_adc *adc = get_irq_desc_data(desc); + uint8_t status; + unsigned int i; + + status = readb(adc->base + JZ_REG_ADC_STATUS); + + for (i = 0; i < 5; ++i) { + if (status & BIT(i)) + generic_handle_irq(adc->irq_base + i); + } +} + + +/* Refcounting for the ADC clock is done in here instead of in the clock + * framework, because it is the only clock which is shared between multiple + * devices and thus is the only clock which needs refcounting */ +static inline void jz4740_adc_clk_enable(struct jz4740_adc *adc) +{ + if (atomic_inc_return(&adc->clk_ref) == 1) + clk_enable(adc->clk); +} + +static inline void jz4740_adc_clk_disable(struct jz4740_adc *adc) +{ + if (atomic_dec_return(&adc->clk_ref) == 0) + clk_disable(adc->clk); +} + +static inline void jz4740_adc_set_enabled(struct jz4740_adc *adc, int engine, + bool enabled) +{ + unsigned long flags; + uint8_t val; + + spin_lock_irqsave(&adc->lock, flags); + + val = readb(adc->base + JZ_REG_ADC_ENABLE); + if (enabled) + val |= BIT(engine); + else + val &= BIT(engine); + writeb(val, adc->base + JZ_REG_ADC_ENABLE); + + spin_unlock_irqrestore(&adc->lock, flags); +} + +static int jz4740_adc_cell_enable(struct platform_device *pdev) +{ + struct jz4740_adc *adc = dev_get_drvdata(pdev->dev.parent); + + jz4740_adc_clk_enable(adc); + jz4740_adc_set_enabled(adc, pdev->id, true); + + return 0; +} + +static int jz4740_adc_cell_disable(struct platform_device *pdev) +{ + struct jz4740_adc *adc = dev_get_drvdata(pdev->dev.parent); + + jz4740_adc_set_enabled(adc, pdev->id, false); + jz4740_adc_clk_disable(adc); + + return 0; +} + +int jz4740_adc_set_config(struct device *dev, uint32_t mask, uint32_t val) +{ + struct jz4740_adc *adc = dev_get_drvdata(dev); + unsigned long flags; + uint32_t cfg; + + if (!adc) + return -ENODEV; + + spin_lock_irqsave(&adc->lock, flags); + + cfg = readl(adc->base + JZ_REG_ADC_CFG); + + cfg &= ~mask; + cfg |= val; + + writel(cfg, adc->base + JZ_REG_ADC_CFG); + + spin_unlock_irqrestore(&adc->lock, flags); + + return 0; +} +EXPORT_SYMBOL_GPL(jz4740_adc_set_config); + +static struct resource jz4740_hwmon_resources[] = { + { + .start = JZ_ADC_IRQ_ADCIN, + .flags = IORESOURCE_IRQ, + }, + { + .start = JZ_REG_ADC_HWMON_BASE, + .end = JZ_REG_ADC_HWMON_BASE + 3, + .flags = IORESOURCE_MEM, + }, +}; + +static struct resource jz4740_battery_resources[] = { + { + .start = JZ_ADC_IRQ_BATTERY, + .flags = IORESOURCE_IRQ, + }, + { + .start = JZ_REG_ADC_BATTERY_BASE, + .end = JZ_REG_ADC_BATTERY_BASE + 3, + .flags = IORESOURCE_MEM, + }, +}; + +const struct mfd_cell jz4740_adc_cells[] = { + { + .id = 0, + .name = "jz4740-hwmon", + .num_resources = ARRAY_SIZE(jz4740_hwmon_resources), + .resources = jz4740_hwmon_resources, + .platform_data = (void *)&jz4740_adc_cells[0], + .data_size = sizeof(struct mfd_cell), + + .enable = jz4740_adc_cell_enable, + .disable = jz4740_adc_cell_disable, + }, + { + .id = 1, + .name = "jz4740-battery", + .num_resources = ARRAY_SIZE(jz4740_battery_resources), + .resources = jz4740_battery_resources, + .platform_data = (void *)&jz4740_adc_cells[1], + .data_size = sizeof(struct mfd_cell), + + .enable = jz4740_adc_cell_enable, + .disable = jz4740_adc_cell_disable, + }, +}; + +static int __devinit jz4740_adc_probe(struct platform_device *pdev) +{ + int ret; + struct jz4740_adc *adc; + struct resource *mem_base; + int irq; + + adc = kmalloc(sizeof(*adc), GFP_KERNEL); + + adc->irq = platform_get_irq(pdev, 0); + if (adc->irq < 0) { + ret = adc->irq; + dev_err(&pdev->dev, "Failed to get platform irq: %d\n", ret); + goto err_free; + } + + adc->irq_base = platform_get_irq(pdev, 1); + if (adc->irq_base < 0) { + ret = adc->irq_base; + dev_err(&pdev->dev, "Failed to get irq base: %d\n", ret); + goto err_free; + } + + mem_base = platform_get_resource(pdev, IORESOURCE_MEM, 0); + if (!mem_base) { + ret = -ENOENT; + dev_err(&pdev->dev, "Failed to get platform mmio resource\n"); + goto err_free; + } + + /* Only request the shared registers for the MFD driver */ + adc->mem = request_mem_region(mem_base->start, JZ_REG_ADC_STATUS, + pdev->name); + if (!adc->mem) { + ret = -EBUSY; + dev_err(&pdev->dev, "Failed to request mmio memory region\n"); + goto err_free; + } + + adc->base = ioremap_nocache(adc->mem->start, resource_size(adc->mem)); + if (!adc->base) { + ret = -EBUSY; + dev_err(&pdev->dev, "Failed to ioremap mmio memory\n"); + goto err_release_mem_region; + } + + adc->clk = clk_get(&pdev->dev, "adc"); + if (IS_ERR(adc->clk)) { + ret = PTR_ERR(adc->clk); + dev_err(&pdev->dev, "Failed to get clock: %d\n", ret); + goto err_iounmap; + } + + spin_lock_init(&adc->lock); + atomic_set(&adc->clk_ref, 0); + + platform_set_drvdata(pdev, adc); + + for (irq = adc->irq_base; irq < adc->irq_base + 5; ++irq) { + set_irq_chip_data(irq, adc); + set_irq_chip_and_handler(irq, &jz4740_adc_irq_chip, + handle_level_irq); + } + + set_irq_data(adc->irq, adc); + set_irq_chained_handler(adc->irq, jz4740_adc_irq_demux); + + writeb(0x00, adc->base + JZ_REG_ADC_ENABLE); + writeb(0xff, adc->base + JZ_REG_ADC_CTRL); + + return mfd_add_devices(&pdev->dev, 0, jz4740_adc_cells, + ARRAY_SIZE(jz4740_adc_cells), mem_base, adc->irq_base); + +err_iounmap: + platform_set_drvdata(pdev, NULL); + iounmap(adc->base); +err_release_mem_region: + release_mem_region(adc->mem->start, resource_size(adc->mem)); +err_free: + kfree(adc); + + return ret; +} + +static int __devexit jz4740_adc_remove(struct platform_device *pdev) +{ + struct jz4740_adc *adc = platform_get_drvdata(pdev); + + mfd_remove_devices(&pdev->dev); + + set_irq_data(adc->irq, NULL); + set_irq_chained_handler(adc->irq, NULL); + + iounmap(adc->base); + release_mem_region(adc->mem->start, resource_size(adc->mem)); + + clk_put(adc->clk); + + platform_set_drvdata(pdev, NULL); + + kfree(adc); + + return 0; +} + +struct platform_driver jz4740_adc_driver = { + .probe = jz4740_adc_probe, + .remove = __devexit_p(jz4740_adc_remove), + .driver = { + .name = "jz4740-adc", + .owner = THIS_MODULE, + }, +}; + +static int __init jz4740_adc_init(void) +{ + return platform_driver_register(&jz4740_adc_driver); +} +module_init(jz4740_adc_init); + +static void __exit jz4740_adc_exit(void) +{ + platform_driver_unregister(&jz4740_adc_driver); +} +module_exit(jz4740_adc_exit); + +MODULE_DESCRIPTION("JZ4740 SoC ADC driver"); +MODULE_AUTHOR("Lars-Peter Clausen "); +MODULE_LICENSE("GPL"); +MODULE_ALIAS("platform:jz4740-adc"); -- cgit v1.2.3