diff options
| -rw-r--r-- | arch/arm/plat-s3c/include/plat/adc.h | 29 | ||||
| -rw-r--r-- | arch/arm/plat-s3c24xx/Kconfig | 7 | ||||
| -rw-r--r-- | arch/arm/plat-s3c24xx/Makefile | 1 | ||||
| -rw-r--r-- | arch/arm/plat-s3c24xx/adc.c | 372 | ||||
| -rw-r--r-- | arch/arm/plat-s3c24xx/devs.c | 10 |
5 files changed, 418 insertions, 1 deletions
diff --git a/arch/arm/plat-s3c/include/plat/adc.h b/arch/arm/plat-s3c/include/plat/adc.h new file mode 100644 index 0000000..43df2a4 --- /dev/null +++ b/arch/arm/plat-s3c/include/plat/adc.h @@ -0,0 +1,29 @@ +/* arch/arm/plat-s3c/include/plat/adc.h + * + * Copyright (c) 2008 Simtec Electronics + * http://armlinux.simnte.co.uk/ + * Ben Dooks <ben@simtec.co.uk> + * + * S3C24XX ADC driver information + * + * 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. +*/ + +#ifndef __ASM_PLAT_ADC_H +#define __ASM_PLAT_ADC_H __FILE__ + +struct s3c_adc_client; + +extern int s3c_adc_start(struct s3c_adc_client *client, + unsigned int channel, unsigned int nr_samples); + +extern struct s3c_adc_client *s3c_adc_register(struct platform_device *pdev, + void (*select)(unsigned selected), + void (*conv)(unsigned d0, unsigned d1), + unsigned int is_ts); + +extern void s3c_adc_release(struct s3c_adc_client *client); + +#endif /* __ASM_PLAT_ADC_H */ diff --git a/arch/arm/plat-s3c24xx/Kconfig b/arch/arm/plat-s3c24xx/Kconfig index d3faf01..7d3d6eb 100644 --- a/arch/arm/plat-s3c24xx/Kconfig +++ b/arch/arm/plat-s3c24xx/Kconfig @@ -62,6 +62,13 @@ config S3C2410_DMA_DEBUG Enable debugging output for the DMA code. This option sends info to the kernel log, at priority KERN_DEBUG. +config S3C24XX_ADC + bool "ADC common driver support" + help + Core support for the ADC block found in the S3C24XX SoC systems + for drivers such as the touchscreen and hwmon to use to share + this resource. + # SPI default pin configuration code config S3C24XX_SPI_BUS0_GPE11_GPE12_GPE13 diff --git a/arch/arm/plat-s3c24xx/Makefile b/arch/arm/plat-s3c24xx/Makefile index 2a65ba7..a8cfdef 100644 --- a/arch/arm/plat-s3c24xx/Makefile +++ b/arch/arm/plat-s3c24xx/Makefile @@ -31,6 +31,7 @@ obj-$(CONFIG_PM) += sleep.o obj-$(CONFIG_HAVE_PWM) += pwm.o obj-$(CONFIG_S3C2410_CLOCK) += s3c2410-clock.o obj-$(CONFIG_S3C2410_DMA) += dma.o +obj-$(CONFIG_S3C24XX_ADC) += adc.o # SPI gpio central GPIO functions diff --git a/arch/arm/plat-s3c24xx/adc.c b/arch/arm/plat-s3c24xx/adc.c new file mode 100644 index 0000000..9a5c767 --- /dev/null +++ b/arch/arm/plat-s3c24xx/adc.c @@ -0,0 +1,372 @@ +/* arch/arm/plat-s3c24xx/adc.c + * + * Copyright (c) 2008 Simtec Electronics + * http://armlinux.simtec.co.uk/ + * Ben Dooks <ben@simtec.co.uk>, <ben-linux@fluff.org> + * + * S3C24XX ADC device core + * + * 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. +*/ + +#include <linux/module.h> +#include <linux/kernel.h> +#include <linux/platform_device.h> +#include <linux/list.h> +#include <linux/err.h> +#include <linux/clk.h> +#include <linux/interrupt.h> +#include <linux/io.h> + +#include <plat/regs-adc.h> +#include <plat/adc.h> + +/* This driver is designed to control the usage of the ADC block between + * the touchscreen and any other drivers that may need to use it, such as + * the hwmon driver. + * + * Priority will be given to the touchscreen driver, but as this itself is + * rate limited it should not starve other requests which are processed in + * order that they are received. + * + * Each user registers to get a client block which uniquely identifies it + * and stores information such as the necessary functions to callback when + * action is required. + */ + +struct s3c_adc_client { + struct platform_device *pdev; + struct list_head pend; + + unsigned int nr_samples; + unsigned char is_ts; + unsigned char channel; + + void (*select_cb)(unsigned selected); + void (*convert_cb)(unsigned val1, unsigned val2); +}; + +struct adc_device { + struct platform_device *pdev; + struct platform_device *owner; + struct clk *clk; + struct s3c_adc_client *cur; + struct s3c_adc_client *ts_pend; + void __iomem *regs; + + unsigned int prescale; + + int irq; +}; + +static struct adc_device *adc_dev; + +static LIST_HEAD(adc_pending); + +#define adc_dbg(_adc, msg...) dev_dbg(&(_adc)->pdev->dev, msg) + +static inline void s3c_adc_convert(struct adc_device *adc) +{ + unsigned con = readl(adc->regs + S3C2410_ADCCON); + + con |= S3C2410_ADCCON_ENABLE_START; + writel(con, adc->regs + S3C2410_ADCCON); +} + +static inline void s3c_adc_select(struct adc_device *adc, + struct s3c_adc_client *client) +{ + unsigned con = readl(adc->regs + S3C2410_ADCCON); + + client->select_cb(1); + + con &= ~S3C2410_ADCCON_MUXMASK; + con &= ~S3C2410_ADCCON_STDBM; + con &= ~S3C2410_ADCCON_STARTMASK; + + if (!client->is_ts) + con |= S3C2410_ADCCON_SELMUX(client->channel); + + writel(con, adc->regs + S3C2410_ADCCON); +} + +static void s3c_adc_dbgshow(struct adc_device *adc) +{ + adc_dbg(adc, "CON=%08x, TSC=%08x, DLY=%08x\n", + readl(adc->regs + S3C2410_ADCCON), + readl(adc->regs + S3C2410_ADCTSC), + readl(adc->regs + S3C2410_ADCDLY)); +} + +void s3c_adc_try(struct adc_device *adc) +{ + struct s3c_adc_client *next = adc->ts_pend; + + if (!next && !list_empty(&adc_pending)) { + next = list_first_entry(&adc_pending, + struct s3c_adc_client, pend); + list_del(&next->pend); + } else + adc->ts_pend = NULL; + + if (next) { + adc_dbg(adc, "new client is %p\n", next); + adc->cur = next; + s3c_adc_select(adc, next); + s3c_adc_convert(adc); + s3c_adc_dbgshow(adc); + } +} + +int s3c_adc_start(struct s3c_adc_client *client, + unsigned int channel, unsigned int nr_samples) +{ + struct adc_device *adc = adc_dev; + unsigned long flags; + + if (!adc) { + printk(KERN_ERR "%s: failed to find adc\n", __func__); + return -EINVAL; + } + + if (client->is_ts && adc->ts_pend) + return -EAGAIN; + + local_irq_save(flags); + + client->channel = channel; + client->nr_samples = nr_samples; + + if (client->is_ts) + adc->ts_pend = client; + else + list_add_tail(&client->pend, &adc_pending); + + if (!adc->cur) + s3c_adc_try(adc); + local_irq_restore(flags); + + return 0; +} +EXPORT_SYMBOL_GPL(s3c_adc_start); + +static void s3c_adc_default_select(unsigned select) +{ +} + +struct s3c_adc_client *s3c_adc_register(struct platform_device *pdev, + void (*select)(unsigned int selected), + void (*conv)(unsigned d0, unsigned d1), + unsigned int is_ts) +{ + struct s3c_adc_client *client; + + WARN_ON(!pdev); + WARN_ON(!conv); + + if (!select) + select = s3c_adc_default_select; + + if (!conv || !pdev) + return ERR_PTR(-EINVAL); + + client = kzalloc(sizeof(struct s3c_adc_client), GFP_KERNEL); + if (!client) { + dev_err(&pdev->dev, "no memory for adc client\n"); + return ERR_PTR(-ENOMEM); + } + + client->pdev = pdev; + client->is_ts = is_ts; + client->select_cb = select; + client->convert_cb = conv; + + return client; +} +EXPORT_SYMBOL_GPL(s3c_adc_register); + +void s3c_adc_release(struct s3c_adc_client *client) +{ + /* We should really check that nothing is in progress. */ + kfree(client); +} +EXPORT_SYMBOL_GPL(s3c_adc_release); + +static irqreturn_t s3c_adc_irq(int irq, void *pw) +{ + struct adc_device *adc = pw; + struct s3c_adc_client *client = adc->cur; + unsigned long flags; + unsigned data0, data1; + + if (!client) { + dev_warn(&adc->pdev->dev, "%s: no adc pending\n", __func__); + return IRQ_HANDLED; + } + + data0 = readl(adc->regs + S3C2410_ADCDAT0); + data1 = readl(adc->regs + S3C2410_ADCDAT1); + adc_dbg(adc, "read %d: 0x%04x, 0x%04x\n", client->nr_samples, data0, data1); + + (client->convert_cb)(data0 & 0x3ff, data1 & 0x3ff); + + if (--client->nr_samples > 0) { + /* fire another conversion for this */ + + client->select_cb(1); + s3c_adc_convert(adc); + } else { + local_irq_save(flags); + (client->select_cb)(0); + adc->cur = NULL; + + s3c_adc_try(adc); + local_irq_restore(flags); + } + + return IRQ_HANDLED; +} + +static int s3c_adc_probe(struct platform_device *pdev) +{ + struct device *dev = &pdev->dev; + struct adc_device *adc; + struct resource *regs; + int ret; + + adc = kzalloc(sizeof(struct adc_device), GFP_KERNEL); + if (adc == NULL) { + dev_err(dev, "failed to allocate adc_device\n"); + return -ENOMEM; + } + + adc->pdev = pdev; + adc->prescale = S3C2410_ADCCON_PRSCVL(49); + + adc->irq = platform_get_irq(pdev, 1); + if (adc->irq <= 0) { + dev_err(dev, "failed to get adc irq\n"); + ret = -ENOENT; + goto err_alloc; + } + + ret = request_irq(adc->irq, s3c_adc_irq, 0, dev_name(dev), adc); + if (ret < 0) { + dev_err(dev, "failed to attach adc irq\n"); + goto err_alloc; + } + + adc->clk = clk_get(dev, "adc"); + if (IS_ERR(adc->clk)) { + dev_err(dev, "failed to get adc clock\n"); + ret = PTR_ERR(adc->clk); + goto err_irq; + } + + regs = platform_get_resource(pdev, IORESOURCE_MEM, 0); + if (!regs) { + dev_err(dev, "failed to find registers\n"); + ret = -ENXIO; + goto err_clk; + } + + adc->regs = ioremap(regs->start, resource_size(regs)); + if (!adc->regs) { + dev_err(dev, "failed to map registers\n"); + ret = -ENXIO; + goto err_clk; + } + + clk_enable(adc->clk); + + writel(adc->prescale | S3C2410_ADCCON_PRSCEN, + adc->regs + S3C2410_ADCCON); + + dev_info(dev, "attached adc driver\n"); + + platform_set_drvdata(pdev, adc); + adc_dev = adc; + + return 0; + + err_clk: + clk_put(adc->clk); + + err_irq: + free_irq(adc->irq, adc); + + err_alloc: + kfree(adc); + return ret; +} + +static int s3c_adc_remove(struct platform_device *pdev) +{ + struct adc_device *adc = platform_get_drvdata(pdev); + + iounmap(adc->regs); + free_irq(adc->irq, adc); + clk_disable(adc->clk); + clk_put(adc->clk); + kfree(adc); + + return 0; +} + +#ifdef CONFIG_PM +static int s3c_adc_suspend(struct platform_device *pdev, pm_message_t state) +{ + struct adc_device *adc = platform_get_drvdata(pdev); + u32 con; + + con = readl(adc->regs + S3C2410_ADCCON); + con |= S3C2410_ADCCON_STDBM; + writel(con, adc->regs + S3C2410_ADCCON); + + clk_disable(adc->clk); + + return 0; +} + +static int s3c_adc_resume(struct platform_device *pdev) +{ + struct adc_device *adc = platform_get_drvdata(pdev); + + clk_enable(adc->clk); + + writel(adc->prescale | S3C2410_ADCCON_PRSCEN, + adc->regs + S3C2410_ADCCON); + + return 0; +} + +#else +#define s3c_adc_suspend NULL +#define s3c_adc_resume NULL +#endif + +static struct platform_driver s3c_adc_driver = { + .driver = { + .name = "s3c24xx-adc", + .owner = THIS_MODULE, + }, + .probe = s3c_adc_probe, + .remove = __devexit_p(s3c_adc_remove), + .suspend = s3c_adc_suspend, + .resume = s3c_adc_resume, +}; + +static int __init adc_init(void) +{ + int ret; + + ret = platform_driver_register(&s3c_adc_driver); + if (ret) + printk(KERN_ERR "%s: failed to add adc driver\n", __func__); + + return ret; +} + +arch_initcall(adc_init); diff --git a/arch/arm/plat-s3c24xx/devs.c b/arch/arm/plat-s3c24xx/devs.c index adf535a..6a33dbc 100644 --- a/arch/arm/plat-s3c24xx/devs.c +++ b/arch/arm/plat-s3c24xx/devs.c @@ -372,12 +372,20 @@ static struct resource s3c_adc_resource[] = { }; struct platform_device s3c_device_adc = { - .name = "s3c2410-adc", + .name = "s3c24xx-adc", .id = -1, .num_resources = ARRAY_SIZE(s3c_adc_resource), .resource = s3c_adc_resource, }; +/* HWMON */ + +struct platform_device s3c_device_hwmon = { + .name = "s3c24xx-hwmon", + .id = -1, + .dev.parent = &s3c_device_adc.dev, +}; + /* SDI */ static struct resource s3c_sdi_resource[] = { |
