+++ /dev/null
-// SPDX-License-Identifier: GPL-1.0+
-//
-// Copyright (c) 2008 Simtec Electronics
-// http://armlinux.simtec.co.uk/
-// Ben Dooks <ben@simtec.co.uk>, <ben-linux@fluff.org>
-//
-// Samsung ADC device core
-
-#include <linux/module.h>
-#include <linux/kernel.h>
-#include <linux/mod_devicetable.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 "regs-adc.h"
-#include <linux/soc/samsung/s3c-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(*client), GFP_KERNEL);
- if (!client)
- 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;
- enum s3c_cpu_type cpu = platform_get_device_id(pdev)->driver_data;
- int ret;
- unsigned tmp;
-
- adc = devm_kzalloc(dev, sizeof(*adc), GFP_KERNEL);
- if (!adc)
- 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)
- 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);
- }
-
- adc->regs = devm_platform_ioremap_resource(pdev, 0);
- if (IS_ERR(adc->regs))
- return PTR_ERR(adc->regs);
-
- ret = regulator_enable(adc->vdd);
- if (ret)
- return ret;
-
- clk_prepare_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_unprepare(adc->clk);
- regulator_disable(adc->vdd);
-
- return 0;
-}
-
-#ifdef CONFIG_PM
-static int s3c_adc_suspend(struct device *dev)
-{
- struct adc_device *adc = dev_get_drvdata(dev);
- 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 = to_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 const 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);
projects / platform / kernel / linux-rpi.git / commitdiff