diff options
author | Maurus Cuelenaere <mcuelenaere@gmail.com> | 2010-01-14 00:30:31 +0100 |
---|---|---|
committer | Ben Dooks <ben-linux@fluff.org> | 2010-01-18 09:30:49 +0900 |
commit | 3929e1e76d9116856a4c7a00fcce0539dd8507a0 (patch) | |
tree | a185da5ed8cff52e08555047b163f2b0d9c66c0f /arch/arm/plat-samsung | |
parent | 501dae90b3ae4dd3d8efdacfcb072c3d65eb5a33 (diff) |
ARM: SAMSUNG: Move S3C24XX ADC driver to plat-samsung
Move S3C24XX ADC driver to plat-samsung
Signed-off-by: Maurus Cuelenaere <mcuelenaere@gmail.com>
Signed-off-by: Ben Dooks <ben-linux@fluff.org>
Diffstat (limited to 'arch/arm/plat-samsung')
-rw-r--r-- | arch/arm/plat-samsung/Kconfig | 9 | ||||
-rw-r--r-- | arch/arm/plat-samsung/Makefile | 4 | ||||
-rw-r--r-- | arch/arm/plat-samsung/adc.c | 435 | ||||
-rw-r--r-- | arch/arm/plat-samsung/include/plat/adc.h | 35 |
4 files changed, 483 insertions, 0 deletions
diff --git a/arch/arm/plat-samsung/Kconfig b/arch/arm/plat-samsung/Kconfig index faec4b8c626..e6c12296735 100644 --- a/arch/arm/plat-samsung/Kconfig +++ b/arch/arm/plat-samsung/Kconfig @@ -74,6 +74,15 @@ config SAMSUNG_GPIO_EXTRA provides. This allows expanding the GPIO space for use with GPIO expanders. +# ADC driver + +config S3C_ADC + bool "ADC common driver support" + help + Core support for the ADC block found in the Samsung SoC systems + for drivers such as the touchscreen and hwmon to use to share + this resource. + # device definitions to compile in config S3C_DEV_HSMMC diff --git a/arch/arm/plat-samsung/Makefile b/arch/arm/plat-samsung/Makefile index aeb7e12d1f6..ee310384b90 100644 --- a/arch/arm/plat-samsung/Makefile +++ b/arch/arm/plat-samsung/Makefile @@ -20,6 +20,10 @@ obj-$(CONFIG_SAMSUNG_CLKSRC) += clock-clksrc.o obj-$(CONFIG_SAMSUNG_IRQ_UART) += irq-uart.o obj-$(CONFIG_SAMSUNG_IRQ_VIC_TIMER) += irq-vic-timer.o +# ADC + +obj-$(CONFIG_S3C_ADC) += adc.o + # devices obj-$(CONFIG_S3C_DEV_HSMMC) += dev-hsmmc.o diff --git a/arch/arm/plat-samsung/adc.c b/arch/arm/plat-samsung/adc.c new file mode 100644 index 00000000000..a8843dd5e1e --- /dev/null +++ b/arch/arm/plat-samsung/adc.c @@ -0,0 +1,435 @@ +/* arch/arm/plat-samsung/adc.c + * + * Copyright (c) 2008 Simtec Electronics + * http://armlinux.simtec.co.uk/ + * Ben Dooks <ben@simtec.co.uk>, <ben-linux@fluff.org> + * + * Samsung 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/sched.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; + wait_queue_head_t *wait; + + unsigned int nr_samples; + int result; + unsigned char is_ts; + unsigned char channel; + + void (*select_cb)(struct s3c_adc_client *c, unsigned selected); + void (*convert_cb)(struct s3c_adc_client *c, + unsigned val1, unsigned val2, + unsigned *samples_left); +}; + +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(client, 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)); +} + +static 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_convert_done(struct s3c_adc_client *client, + unsigned v, unsigned u, unsigned *left) +{ + client->result = v; + wake_up(client->wait); +} + +int s3c_adc_read(struct s3c_adc_client *client, unsigned int ch) +{ + DECLARE_WAIT_QUEUE_HEAD_ONSTACK(wake); + int ret; + + client->convert_cb = s3c_convert_done; + client->wait = &wake; + client->result = -1; + + ret = s3c_adc_start(client, ch, 1); + if (ret < 0) + goto err; + + ret = wait_event_timeout(wake, client->result >= 0, HZ / 2); + if (client->result < 0) { + ret = -ETIMEDOUT; + goto err; + } + + client->convert_cb = NULL; + return client->result; + +err: + return ret; +} +EXPORT_SYMBOL_GPL(s3c_adc_read); + +static void s3c_adc_default_select(struct s3c_adc_client *client, + unsigned select) +{ +} + +struct s3c_adc_client *s3c_adc_register(struct platform_device *pdev, + void (*select)(struct s3c_adc_client *client, + unsigned int selected), + void (*conv)(struct s3c_adc_client *client, + unsigned d0, unsigned d1, + unsigned *samples_left), + unsigned int is_ts) +{ + struct s3c_adc_client *client; + + WARN_ON(!pdev); + + if (!select) + select = s3c_adc_default_select; + + if (!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. */ + if (adc_dev->cur == client) + adc_dev->cur = NULL; + if (adc_dev->ts_pend == client) + adc_dev->ts_pend = NULL; + else { + struct list_head *p, *n; + struct s3c_adc_client *tmp; + + list_for_each_safe(p, n, &adc_pending) { + tmp = list_entry(p, struct s3c_adc_client, pend); + if (tmp == client) + list_del(&tmp->pend); + } + } + + if (adc_dev->cur == NULL) + s3c_adc_try(adc_dev); + 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->nr_samples--; + + if (client->convert_cb) + (client->convert_cb)(client, data0 & 0x3ff, data1 & 0x3ff, + &client->nr_samples); + + if (client->nr_samples > 0) { + /* fire another conversion for this */ + + client->select_cb(client, 1); + s3c_adc_convert(adc); + } else { + local_irq_save(flags); + (client->select_cb)(client, 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 __devexit 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-samsung/include/plat/adc.h b/arch/arm/plat-samsung/include/plat/adc.h new file mode 100644 index 00000000000..e8382c7be10 --- /dev/null +++ b/arch/arm/plat-samsung/include/plat/adc.h @@ -0,0 +1,35 @@ +/* arch/arm/plat-samsung/include/plat/adc.h + * + * Copyright (c) 2008 Simtec Electronics + * http://armlinux.simnte.co.uk/ + * Ben Dooks <ben@simtec.co.uk> + * + * S3C 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 int s3c_adc_read(struct s3c_adc_client *client, unsigned int ch); + +extern struct s3c_adc_client * + s3c_adc_register(struct platform_device *pdev, + void (*select)(struct s3c_adc_client *client, + unsigned selected), + void (*conv)(struct s3c_adc_client *client, + unsigned d0, unsigned d1, + unsigned *samples_left), + unsigned int is_ts); + +extern void s3c_adc_release(struct s3c_adc_client *client); + +#endif /* __ASM_PLAT_ADC_H */ |