--- /dev/null
+/* 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/slab.h>
+#include <linux/err.h>
+#include <linux/clk.h>
+#include <linux/interrupt.h>
+#include <linux/io.h>
+#include <linux/regulator/consumer.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.
+ */
+
+enum s3c_cpu_type {
+ TYPE_ADCV1, /* S3C24XX */
+ TYPE_ADCV11, /* S3C2443 */
+ TYPE_ADCV12, /* S3C2416, S3C2450 */
+ TYPE_ADCV2, /* S3C64XX */
+ TYPE_ADCV3, /* S5PV210, S5PC110, EXYNOS4210 */
+};
+
+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;
+ spinlock_t lock;
+
+ unsigned int prescale;
+
+ int irq;
+ struct regulator *vdd;
+};
+
+static struct adc_device *adc_dev;
+
+static LIST_HEAD(adc_pending); /* protected by adc_device.lock */
+
+#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);
+ enum s3c_cpu_type cpu = platform_get_device_id(adc->pdev)->driver_data;
+
+ client->select_cb(client, 1);
+
+ if (cpu == TYPE_ADCV1 || cpu == TYPE_ADCV2)
+ con &= ~S3C2410_ADCCON_MUXMASK;
+ con &= ~S3C2410_ADCCON_STDBM;
+ con &= ~S3C2410_ADCCON_STARTMASK;
+
+ if (!client->is_ts) {
+ if (cpu == TYPE_ADCV3)
+ writel(client->channel & 0xf, adc->regs + S5P_ADCMUX);
+ else if (cpu == TYPE_ADCV11 || cpu == TYPE_ADCV12)
+ writel(client->channel & 0xf,
+ adc->regs + S3C2443_ADCMUX);
+ else
+ 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;
+ }
+
+ spin_lock_irqsave(&adc->lock, flags);
+
+ if (client->is_ts && adc->ts_pend) {
+ spin_unlock_irqrestore(&adc->lock, flags);
+ return -EAGAIN;
+ }
+
+ 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);
+
+ spin_unlock_irqrestore(&adc->lock, 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)
+{
+ unsigned long flags;
+
+ spin_lock_irqsave(&adc_dev->lock, flags);
+
+ /* 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);
+
+ spin_unlock_irqrestore(&adc_dev->lock, flags);
+ 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;
+ enum s3c_cpu_type cpu = platform_get_device_id(adc->pdev)->driver_data;
+ unsigned data0, data1;
+
+ if (!client) {
+ dev_warn(&adc->pdev->dev, "%s: no adc pending\n", __func__);
+ goto exit;
+ }
+
+ 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 (cpu == TYPE_ADCV1 || cpu == TYPE_ADCV11) {
+ data0 &= 0x3ff;
+ data1 &= 0x3ff;
+ } else {
+ /* S3C2416/S3C64XX/S5P ADC resolution is 12-bit */
+ data0 &= 0xfff;
+ data1 &= 0xfff;
+ }
+
+ if (client->convert_cb)
+ (client->convert_cb)(client, data0, data1, &client->nr_samples);
+
+ if (client->nr_samples > 0) {
+ /* fire another conversion for this */
+
+ client->select_cb(client, 1);
+ s3c_adc_convert(adc);
+ } else {
+ spin_lock(&adc->lock);
+ (client->select_cb)(client, 0);
+ adc->cur = NULL;
+
+ s3c_adc_try(adc);
+ spin_unlock(&adc->lock);
+ }
+
+exit:
+ if (cpu == TYPE_ADCV2 || cpu == TYPE_ADCV3) {
+ /* Clear ADC interrupt */
+ writel(0, adc->regs + S3C64XX_ADCCLRINT);
+ }
+ return IRQ_HANDLED;
+}
+
+static int s3c_adc_probe(struct platform_device *pdev)
+{
+ struct device *dev = &pdev->dev;
+ struct adc_device *adc;
+ struct resource *regs;
+ enum s3c_cpu_type cpu = platform_get_device_id(pdev)->driver_data;
+ int ret;
+ unsigned tmp;
+
+ adc = devm_kzalloc(dev, sizeof(struct adc_device), GFP_KERNEL);
+ if (adc == NULL) {
+ dev_err(dev, "failed to allocate adc_device\n");
+ return -ENOMEM;
+ }
+
+ spin_lock_init(&adc->lock);
+
+ adc->pdev = pdev;
+ adc->prescale = S3C2410_ADCCON_PRSCVL(49);
+
+ adc->vdd = devm_regulator_get(dev, "vdd");
+ if (IS_ERR(adc->vdd)) {
+ dev_err(dev, "operating without regulator \"vdd\" .\n");
+ return PTR_ERR(adc->vdd);
+ }
+
+ adc->irq = platform_get_irq(pdev, 1);
+ if (adc->irq <= 0) {
+ dev_err(dev, "failed to get adc irq\n");
+ return -ENOENT;
+ }
+
+ ret = devm_request_irq(dev, adc->irq, s3c_adc_irq, 0, dev_name(dev),
+ adc);
+ if (ret < 0) {
+ dev_err(dev, "failed to attach adc irq\n");
+ return ret;
+ }
+
+ adc->clk = devm_clk_get(dev, "adc");
+ if (IS_ERR(adc->clk)) {
+ dev_err(dev, "failed to get adc clock\n");
+ return PTR_ERR(adc->clk);
+ }
+
+ regs = platform_get_resource(pdev, IORESOURCE_MEM, 0);
+ adc->regs = devm_ioremap_resource(dev, regs);
+ if (IS_ERR(adc->regs))
+ return PTR_ERR(adc->regs);
+
+ ret = regulator_enable(adc->vdd);
+ if (ret)
+ return ret;
+
+ clk_enable(adc->clk);
+
+ tmp = adc->prescale | S3C2410_ADCCON_PRSCEN;
+
+ /* Enable 12-bit ADC resolution */
+ if (cpu == TYPE_ADCV12)
+ tmp |= S3C2416_ADCCON_RESSEL;
+ if (cpu == TYPE_ADCV2 || cpu == TYPE_ADCV3)
+ tmp |= S3C64XX_ADCCON_RESSEL;
+
+ writel(tmp, adc->regs + S3C2410_ADCCON);
+
+ dev_info(dev, "attached adc driver\n");
+
+ platform_set_drvdata(pdev, adc);
+ adc_dev = adc;
+
+ return 0;
+}
+
+static int s3c_adc_remove(struct platform_device *pdev)
+{
+ struct adc_device *adc = platform_get_drvdata(pdev);
+
+ clk_disable(adc->clk);
+ regulator_disable(adc->vdd);
+
+ return 0;
+}
+
+#ifdef CONFIG_PM
+static int s3c_adc_suspend(struct device *dev)
+{
+ struct platform_device *pdev = container_of(dev,
+ struct platform_device, dev);
+ struct adc_device *adc = platform_get_drvdata(pdev);
+ unsigned long flags;
+ u32 con;
+
+ spin_lock_irqsave(&adc->lock, flags);
+
+ con = readl(adc->regs + S3C2410_ADCCON);
+ con |= S3C2410_ADCCON_STDBM;
+ writel(con, adc->regs + S3C2410_ADCCON);
+
+ disable_irq(adc->irq);
+ spin_unlock_irqrestore(&adc->lock, flags);
+ clk_disable(adc->clk);
+ regulator_disable(adc->vdd);
+
+ return 0;
+}
+
+static int s3c_adc_resume(struct device *dev)
+{
+ struct platform_device *pdev = container_of(dev,
+ struct platform_device, dev);
+ struct adc_device *adc = platform_get_drvdata(pdev);
+ enum s3c_cpu_type cpu = platform_get_device_id(pdev)->driver_data;
+ int ret;
+ unsigned long tmp;
+
+ ret = regulator_enable(adc->vdd);
+ if (ret)
+ return ret;
+ clk_enable(adc->clk);
+ enable_irq(adc->irq);
+
+ tmp = adc->prescale | S3C2410_ADCCON_PRSCEN;
+
+ /* Enable 12-bit ADC resolution */
+ if (cpu == TYPE_ADCV12)
+ tmp |= S3C2416_ADCCON_RESSEL;
+ if (cpu == TYPE_ADCV2 || cpu == TYPE_ADCV3)
+ tmp |= S3C64XX_ADCCON_RESSEL;
+
+ writel(tmp, adc->regs + S3C2410_ADCCON);
+
+ return 0;
+}
+
+#else
+#define s3c_adc_suspend NULL
+#define s3c_adc_resume NULL
+#endif
+
+static struct platform_device_id s3c_adc_driver_ids[] = {
+ {
+ .name = "s3c24xx-adc",
+ .driver_data = TYPE_ADCV1,
+ }, {
+ .name = "s3c2443-adc",
+ .driver_data = TYPE_ADCV11,
+ }, {
+ .name = "s3c2416-adc",
+ .driver_data = TYPE_ADCV12,
+ }, {
+ .name = "s3c64xx-adc",
+ .driver_data = TYPE_ADCV2,
+ }, {
+ .name = "samsung-adc-v3",
+ .driver_data = TYPE_ADCV3,
+ },
+ { }
+};
+MODULE_DEVICE_TABLE(platform, s3c_adc_driver_ids);
+
+static const struct dev_pm_ops adc_pm_ops = {
+ .suspend = s3c_adc_suspend,
+ .resume = s3c_adc_resume,
+};
+
+static struct platform_driver s3c_adc_driver = {
+ .id_table = s3c_adc_driver_ids,
+ .driver = {
+ .name = "s3c-adc",
+ .pm = &adc_pm_ops,
+ },
+ .probe = s3c_adc_probe,
+ .remove = s3c_adc_remove,
+};
+
+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;
+}
+
+module_init(adc_init);
Code Review / kvmfornfv.git / blobdiff