--- /dev/null
+/*
+ * drivers/i2c/chips/twl4030-madc.c
+ *
+ * TWL4030 MADC module driver
+ *
+ * Copyright (C) 2008 Nokia Corporation
+ * Mikko Ylinen <mikko.k.ylinen@nokia.com>
+ *
+ * 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.
+ *
+ * This program is distributed in the hope that it will be useful, but
+ * WITHOUT ANY WARRANTY; without even the implied warranty of
+ * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the GNU
+ * General Public License for more details.
+ *
+ * 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., 51 Franklin St, Fifth Floor, Boston, MA
+ * 02110-1301 USA
+ *
+ */
+
+#include <linux/init.h>
+#include <linux/interrupt.h>
+#include <linux/kernel.h>
+#include <linux/types.h>
+#include <linux/module.h>
+#include <linux/delay.h>
+#include <linux/fs.h>
+#include <linux/platform_device.h>
+#include <linux/miscdevice.h>
+#include <linux/i2c/twl4030.h>
+#include <linux/i2c/twl4030-madc.h>
+
+#include <asm/uaccess.h>
+
+#define TWL4030_MADC_PFX "twl4030-madc: "
+
+struct twl4030_madc_data {
+ struct device *dev;
+ struct mutex lock;
+ struct work_struct ws;
+ struct twl4030_madc_request requests[TWL4030_MADC_NUM_METHODS];
+ int imr;
+ int isr;
+};
+
+static struct twl4030_madc_data *the_madc;
+
+static
+const struct twl4030_madc_conversion_method twl4030_conversion_methods[] = {
+ [TWL4030_MADC_RT] = {
+ .sel = TWL4030_MADC_RTSELECT_LSB,
+ .avg = TWL4030_MADC_RTAVERAGE_LSB,
+ .rbase = TWL4030_MADC_RTCH0_LSB,
+ },
+ [TWL4030_MADC_SW1] = {
+ .sel = TWL4030_MADC_SW1SELECT_LSB,
+ .avg = TWL4030_MADC_SW1AVERAGE_LSB,
+ .rbase = TWL4030_MADC_GPCH0_LSB,
+ .ctrl = TWL4030_MADC_CTRL_SW1,
+ },
+ [TWL4030_MADC_SW2] = {
+ .sel = TWL4030_MADC_SW2SELECT_LSB,
+ .avg = TWL4030_MADC_SW2AVERAGE_LSB,
+ .rbase = TWL4030_MADC_GPCH0_LSB,
+ .ctrl = TWL4030_MADC_CTRL_SW2,
+ },
+};
+
+static int twl4030_madc_read(struct twl4030_madc_data *madc, u8 reg)
+{
+ int ret;
+ u8 val;
+
+ ret = twl4030_i2c_read_u8(TWL4030_MODULE_MADC, &val, reg);
+ if (ret) {
+ dev_dbg(madc->dev, "unable to read register 0x%X\n", reg);
+ return ret;
+ }
+
+ return val;
+}
+
+static void twl4030_madc_write(struct twl4030_madc_data *madc, u8 reg, u8 val)
+{
+ int ret;
+
+ ret = twl4030_i2c_write_u8(TWL4030_MODULE_MADC, val, reg);
+ if (ret)
+ dev_err(madc->dev, "unable to write register 0x%X\n", reg);
+}
+
+static int twl4030_madc_channel_raw_read(struct twl4030_madc_data *madc, u8 reg)
+{
+ u8 msb, lsb;
+
+ /* For each ADC channel, we have MSB and LSB register pair. MSB address
+ * is always LSB address+1. reg parameter is the addr of LSB register */
+ msb = twl4030_madc_read(madc, reg + 1);
+ lsb = twl4030_madc_read(madc, reg);
+
+ return (int)(((msb << 8) | lsb) >> 6);
+}
+
+static int twl4030_madc_read_channels(struct twl4030_madc_data *madc,
+ u8 reg_base, u16 channels, int *buf)
+{
+ int count = 0;
+ u8 reg, i;
+
+ if (unlikely(!buf))
+ return 0;
+
+ for (i = 0; i < TWL4030_MADC_MAX_CHANNELS; i++) {
+ if (channels & (1<<i)) {
+ reg = reg_base + 2*i;
+ buf[i] = twl4030_madc_channel_raw_read(madc, reg);
+ count++;
+ }
+ }
+ return count;
+}
+
+static void twl4030_madc_enable_irq(struct twl4030_madc_data *madc, int id)
+{
+ u8 val;
+
+ val = twl4030_madc_read(madc, madc->imr);
+ val &= ~(1 << id);
+ twl4030_madc_write(madc, madc->imr, val);
+}
+
+static void twl4030_madc_disable_irq(struct twl4030_madc_data *madc, int id)
+{
+ u8 val;
+
+ val = twl4030_madc_read(madc, madc->imr);
+ val |= (1 << id);
+ twl4030_madc_write(madc, madc->imr, val);
+}
+
+static irqreturn_t twl4030_madc_irq_handler(int irq, void *_madc)
+{
+ struct twl4030_madc_data *madc = _madc;
+ u8 isr_val, imr_val;
+ int i;
+
+#ifdef CONFIG_LOCKDEP
+ /* WORKAROUND for lockdep forcing IRQF_DISABLED on us, which
+ * we don't want and can't tolerate. Although it might be
+ * friendlier not to borrow this thread context...
+ */
+ local_irq_enable();
+#endif
+
+ /* Use COR to ack interrupts since we have no shared IRQs in ISRx */
+ isr_val = twl4030_madc_read(madc, madc->isr);
+ imr_val = twl4030_madc_read(madc, madc->imr);
+
+ isr_val &= ~imr_val;
+
+ for (i = 0; i < TWL4030_MADC_NUM_METHODS; i++) {
+
+ if (!(isr_val & (1<<i)))
+ continue;
+
+ twl4030_madc_disable_irq(madc, i);
+ madc->requests[i].result_pending = 1;
+ }
+
+ schedule_work(&madc->ws);
+
+ return IRQ_HANDLED;
+}
+
+static void twl4030_madc_work(struct work_struct *ws)
+{
+ const struct twl4030_madc_conversion_method *method;
+ struct twl4030_madc_data *madc;
+ struct twl4030_madc_request *r;
+ int len, i;
+
+ madc = container_of(ws, struct twl4030_madc_data, ws);
+ mutex_lock(&madc->lock);
+
+ for (i = 0; i < TWL4030_MADC_NUM_METHODS; i++) {
+
+ r = &madc->requests[i];
+
+ /* No pending results for this method, move to next one */
+ if (!r->result_pending)
+ continue;
+
+ method = &twl4030_conversion_methods[r->method];
+
+ /* Read results */
+ len = twl4030_madc_read_channels(madc, method->rbase,
+ r->channels, r->rbuf);
+
+ /* Return results to caller */
+ if (r->func_cb != NULL) {
+ r->func_cb(len, r->channels, r->rbuf);
+ r->func_cb = NULL;
+ }
+
+ /* Free request */
+ r->result_pending = 0;
+ r->active = 0;
+ }
+
+ mutex_unlock(&madc->lock);
+}
+
+static int twl4030_madc_set_irq(struct twl4030_madc_data *madc,
+ struct twl4030_madc_request *req)
+{
+ struct twl4030_madc_request *p;
+
+ p = &madc->requests[req->method];
+
+ memcpy(p, req, sizeof *req);
+
+ twl4030_madc_enable_irq(madc, req->method);
+
+ return 0;
+}
+
+static inline void twl4030_madc_start_conversion(struct twl4030_madc_data *madc,
+ int conv_method)
+{
+ const struct twl4030_madc_conversion_method *method;
+
+ method = &twl4030_conversion_methods[conv_method];
+
+ switch (conv_method) {
+ case TWL4030_MADC_SW1:
+ case TWL4030_MADC_SW2:
+ twl4030_madc_write(madc, method->ctrl, TWL4030_MADC_SW_START);
+ break;
+ case TWL4030_MADC_RT:
+ default:
+ break;
+ }
+}
+
+static int twl4030_madc_wait_conversion_ready(
+ struct twl4030_madc_data *madc,
+ unsigned int timeout_ms, u8 status_reg)
+{
+ unsigned long timeout;
+
+ timeout = jiffies + msecs_to_jiffies(timeout_ms);
+ do {
+ u8 reg;
+
+ reg = twl4030_madc_read(madc, status_reg);
+ if (!(reg & TWL4030_MADC_BUSY) && (reg & TWL4030_MADC_EOC_SW))
+ return 0;
+ } while (!time_after(jiffies, timeout));
+
+ return -EAGAIN;
+}
+
+int twl4030_madc_conversion(struct twl4030_madc_request *req)
+{
+ const struct twl4030_madc_conversion_method *method;
+ u8 ch_msb, ch_lsb;
+ int ret;
+
+ if (unlikely(!req))
+ return -EINVAL;
+
+ mutex_lock(&the_madc->lock);
+
+ /* Do we have a conversion request ongoing */
+ if (the_madc->requests[req->method].active) {
+ ret = -EBUSY;
+ goto out;
+ }
+
+ ch_msb = (req->channels >> 8) & 0xff;
+ ch_lsb = req->channels & 0xff;
+
+ method = &twl4030_conversion_methods[req->method];
+
+ /* Select channels to be converted */
+ twl4030_madc_write(the_madc, method->sel + 1, ch_msb);
+ twl4030_madc_write(the_madc, method->sel, ch_lsb);
+
+ /* Select averaging for all channels if do_avg is set */
+ if (req->do_avg) {
+ twl4030_madc_write(the_madc, method->avg + 1, ch_msb);
+ twl4030_madc_write(the_madc, method->avg, ch_lsb);
+ }
+
+ if ((req->type == TWL4030_MADC_IRQ_ONESHOT) && (req->func_cb != NULL)) {
+ twl4030_madc_set_irq(the_madc, req);
+ twl4030_madc_start_conversion(the_madc, req->method);
+ the_madc->requests[req->method].active = 1;
+ ret = 0;
+ goto out;
+ }
+
+ /* With RT method we should not be here anymore */
+ if (req->method == TWL4030_MADC_RT) {
+ ret = -EINVAL;
+ goto out;
+ }
+
+ twl4030_madc_start_conversion(the_madc, req->method);
+ the_madc->requests[req->method].active = 1;
+
+ /* Wait until conversion is ready (ctrl register returns EOC) */
+ ret = twl4030_madc_wait_conversion_ready(the_madc, 5, method->ctrl);
+ if (ret) {
+ dev_dbg(the_madc->dev, "conversion timeout!\n");
+ the_madc->requests[req->method].active = 0;
+ goto out;
+ }
+
+ ret = twl4030_madc_read_channels(the_madc, method->rbase, req->channels,
+ req->rbuf);
+
+ the_madc->requests[req->method].active = 0;
+
+out:
+ mutex_unlock(&the_madc->lock);
+
+ return ret;
+}
+EXPORT_SYMBOL(twl4030_madc_conversion);
+
+static int twl4030_madc_set_current_generator(struct twl4030_madc_data *madc,
+ int chan, int on)
+{
+ int ret;
+ u8 regval;
+
+ /* Current generator is only available for ADCIN0 and ADCIN1. NB:
+ * ADCIN1 current generator only works when AC or VBUS is present */
+ if (chan > 1)
+ return EINVAL;
+
+ ret = twl4030_i2c_read_u8(TWL4030_MODULE_MAIN_CHARGE,
+ ®val, TWL4030_BCI_BCICTL1);
+ if (on)
+ regval |= (chan) ? TWL4030_BCI_ITHEN : TWL4030_BCI_TYPEN;
+ else
+ regval &= (chan) ? ~TWL4030_BCI_ITHEN : ~TWL4030_BCI_TYPEN;
+ ret = twl4030_i2c_write_u8(TWL4030_MODULE_MAIN_CHARGE,
+ regval, TWL4030_BCI_BCICTL1);
+
+ return ret;
+}
+
+static int twl4030_madc_set_power(struct twl4030_madc_data *madc, int on)
+{
+ u8 regval;
+
+ regval = twl4030_madc_read(madc, TWL4030_MADC_CTRL1);
+ if (on)
+ regval |= TWL4030_MADC_MADCON;
+ else
+ regval &= ~TWL4030_MADC_MADCON;
+ twl4030_madc_write(madc, TWL4030_MADC_CTRL1, regval);
+
+ return 0;
+}
+
+static long twl4030_madc_ioctl(struct file *filp, unsigned int cmd,
+ unsigned long arg)
+{
+ struct twl4030_madc_user_parms par;
+ int val, ret;
+
+ ret = copy_from_user(&par, (void __user *) arg, sizeof(par));
+ if (ret) {
+ dev_dbg(the_madc->dev, "copy_from_user: %d\n", ret);
+ return -EACCES;
+ }
+
+ switch (cmd) {
+ case TWL4030_MADC_IOCX_ADC_RAW_READ: {
+ struct twl4030_madc_request req;
+ if (par.channel >= TWL4030_MADC_MAX_CHANNELS)
+ return -EINVAL;
+
+ req.channels = (1 << par.channel);
+ req.do_avg = par.average;
+ req.method = TWL4030_MADC_SW1;
+ req.func_cb = NULL;
+
+ val = twl4030_madc_conversion(&req);
+ if (val <= 0) {
+ par.status = -1;
+ } else {
+ par.status = 0;
+ par.result = (u16)req.rbuf[par.channel];
+ }
+ break;
+ }
+ default:
+ return -EINVAL;
+ }
+
+ ret = copy_to_user((void __user *) arg, &par, sizeof(par));
+ if (ret) {
+ dev_dbg(the_madc->dev, "copy_to_user: %d\n", ret);
+ return -EACCES;
+ }
+
+ return 0;
+}
+
+static struct file_operations twl4030_madc_fileops = {
+ .owner = THIS_MODULE,
+ .unlocked_ioctl = twl4030_madc_ioctl
+};
+
+static struct miscdevice twl4030_madc_device = {
+ .minor = MISC_DYNAMIC_MINOR,
+ .name = "twl4030-madc",
+ .fops = &twl4030_madc_fileops
+};
+
+static int __init twl4030_madc_probe(struct platform_device *pdev)
+{
+ struct twl4030_madc_data *madc;
+ struct twl4030_madc_platform_data *pdata = pdev->dev.platform_data;
+ int ret;
+ u8 regval;
+
+ madc = kzalloc(sizeof *madc, GFP_KERNEL);
+ if (!madc)
+ return -ENOMEM;
+
+ if (!pdata) {
+ dev_dbg(&pdev->dev, "platform_data not available\n");
+ ret = -EINVAL;
+ goto err_pdata;
+ }
+
+ madc->imr = (pdata->irq_line == 1) ? TWL4030_MADC_IMR1 : TWL4030_MADC_IMR2;
+ madc->isr = (pdata->irq_line == 1) ? TWL4030_MADC_ISR1 : TWL4030_MADC_ISR2;
+
+ ret = misc_register(&twl4030_madc_device);
+ if (ret) {
+ dev_dbg(&pdev->dev, "could not register misc_device\n");
+ goto err_misc;
+ }
+ twl4030_madc_set_power(madc, 1);
+ twl4030_madc_set_current_generator(madc, 0, 1);
+
+ ret = twl4030_i2c_read_u8(TWL4030_MODULE_MAIN_CHARGE,
+ ®val, TWL4030_BCI_BCICTL1);
+
+ regval |= TWL4030_BCI_MESBAT;
+
+ ret = twl4030_i2c_write_u8(TWL4030_MODULE_MAIN_CHARGE,
+ regval, TWL4030_BCI_BCICTL1);
+
+ ret = request_irq(platform_get_irq(pdev, 0), twl4030_madc_irq_handler,
+ 0, "twl4030_madc", madc);
+ if (ret) {
+ dev_dbg(&pdev->dev, "could not request irq\n");
+ goto err_irq;
+ }
+
+ platform_set_drvdata(pdev, madc);
+ mutex_init(&madc->lock);
+ INIT_WORK(&madc->ws, twl4030_madc_work);
+
+ the_madc = madc;
+
+ return 0;
+
+err_irq:
+ misc_deregister(&twl4030_madc_device);
+
+err_misc:
+err_pdata:
+ kfree(madc);
+
+ return ret;
+}
+
+static int __exit twl4030_madc_remove(struct platform_device *pdev)
+{
+ struct twl4030_madc_data *madc = platform_get_drvdata(pdev);
+
+ twl4030_madc_set_power(madc, 0);
+ twl4030_madc_set_current_generator(madc, 0, 0);
+ free_irq(platform_get_irq(pdev, 0), madc);
+ cancel_work_sync(&madc->ws);
+ misc_deregister(&twl4030_madc_device);
+
+ return 0;
+}
+
+static struct platform_driver twl4030_madc_driver = {
+ .probe = twl4030_madc_probe,
+ .remove = __exit_p(twl4030_madc_remove),
+ .driver = {
+ .name = "twl4030_madc",
+ .owner = THIS_MODULE,
+ },
+};
+
+static int __init twl4030_madc_init(void)
+{
+ return platform_driver_register(&twl4030_madc_driver);
+}
+module_init(twl4030_madc_init);
+
+static void __exit twl4030_madc_exit(void)
+{
+ platform_driver_unregister(&twl4030_madc_driver);
+}
+module_exit(twl4030_madc_exit);
+
+MODULE_ALIAS("platform:twl4030-madc");
+MODULE_AUTHOR("Nokia Corporation");
+MODULE_DESCRIPTION("twl4030 ADC driver");
+MODULE_LICENSE("GPL");
+
projects / linux-2.6-omap-h63xx.git / blobdiff