mfd: Add twl4030 madc driver
authorKeerthy <j-keerthy@ti.com>
Tue, 1 Mar 2011 13:42:26 +0000 (19:12 +0530)
committerSamuel Ortiz <sameo@linux.intel.com>
Wed, 23 Mar 2011 09:42:00 +0000 (10:42 +0100)
Introducing a driver for MADC on TWL4030 powerIC. MADC stands for monitoring
ADC. This driver monitors the real time conversion of analog signals like
battery temperature, battery cuurent etc.

Signed-off-by: Keerthy <j-keerthy@ti.com>
Signed-off-by: Samuel Ortiz <sameo@linux.intel.com>
drivers/mfd/Kconfig
drivers/mfd/Makefile
drivers/mfd/twl4030-madc.c [new file with mode: 0644]
include/linux/i2c/twl4030-madc.h [new file with mode: 0644]

index d71af45..50c4769 100644 (file)
@@ -178,6 +178,16 @@ config TWL4030_CORE
          high speed USB OTG transceiver, an audio codec (on most
          versions) and many other features.
 
+config TWL4030_MADC
+       tristate "Texas Instruments TWL4030 MADC"
+       depends on TWL4030_CORE
+       help
+       This driver provides support for triton TWL4030-MADC. The
+       driver supports both RT and SW conversion methods.
+
+       This driver can be built as a module. If so it will be
+       named twl4030-madc
+
 config TWL4030_POWER
        bool "Support power resources on TWL4030 family chips"
        depends on TWL4030_CORE && ARM
index ad71bd5..25f3c75 100644 (file)
@@ -38,6 +38,7 @@ obj-$(CONFIG_TPS6507X)                += tps6507x.o
 obj-$(CONFIG_MENELAUS)         += menelaus.o
 
 obj-$(CONFIG_TWL4030_CORE)     += twl-core.o twl4030-irq.o twl6030-irq.o
+obj-$(CONFIG_TWL4030_MADC)      += twl4030-madc.o
 obj-$(CONFIG_TWL4030_POWER)    += twl4030-power.o
 obj-$(CONFIG_TWL4030_CODEC)    += twl4030-codec.o
 obj-$(CONFIG_TWL6030_PWM)      += twl6030-pwm.o
diff --git a/drivers/mfd/twl4030-madc.c b/drivers/mfd/twl4030-madc.c
new file mode 100644 (file)
index 0000000..e9884e2
--- /dev/null
@@ -0,0 +1,802 @@
+/*
+ *
+ * TWL4030 MADC module driver-This driver monitors the real time
+ * conversion of analog signals like battery temperature,
+ * battery type, battery level etc.
+ *
+ * Copyright (C) 2011 Texas Instruments Incorporated - http://www.ti.com/
+ * J Keerthy <j-keerthy@ti.com>
+ *
+ * Based on twl4030-madc.c
+ * Copyright (C) 2008 Nokia Corporation
+ * Mikko Ylinen <mikko.k.ylinen@nokia.com>
+ *
+ * Amit Kucheria <amit.kucheria@canonical.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/device.h>
+#include <linux/interrupt.h>
+#include <linux/kernel.h>
+#include <linux/delay.h>
+#include <linux/platform_device.h>
+#include <linux/slab.h>
+#include <linux/i2c/twl.h>
+#include <linux/i2c/twl4030-madc.h>
+#include <linux/module.h>
+#include <linux/stddef.h>
+#include <linux/mutex.h>
+#include <linux/bitops.h>
+#include <linux/jiffies.h>
+#include <linux/types.h>
+#include <linux/gfp.h>
+#include <linux/err.h>
+
+/*
+ * struct twl4030_madc_data - a container for madc info
+ * @dev - pointer to device structure for madc
+ * @lock - mutex protecting this data structure
+ * @requests - Array of request struct corresponding to SW1, SW2 and RT
+ * @imr - Interrupt mask register of MADC
+ * @isr - Interrupt status register of MADC
+ */
+struct twl4030_madc_data {
+       struct device *dev;
+       struct mutex lock;      /* mutex protecting this data structure */
+       struct twl4030_madc_request requests[TWL4030_MADC_NUM_METHODS];
+       int imr;
+       int isr;
+};
+
+static struct twl4030_madc_data *twl4030_madc;
+
+struct twl4030_prescale_divider_ratios {
+       s16 numerator;
+       s16 denominator;
+};
+
+static const struct twl4030_prescale_divider_ratios
+twl4030_divider_ratios[16] = {
+       {1, 1},         /* CHANNEL 0 No Prescaler */
+       {1, 1},         /* CHANNEL 1 No Prescaler */
+       {6, 10},        /* CHANNEL 2 */
+       {6, 10},        /* CHANNEL 3 */
+       {6, 10},        /* CHANNEL 4 */
+       {6, 10},        /* CHANNEL 5 */
+       {6, 10},        /* CHANNEL 6 */
+       {6, 10},        /* CHANNEL 7 */
+       {3, 14},        /* CHANNEL 8 */
+       {1, 3},         /* CHANNEL 9 */
+       {1, 1},         /* CHANNEL 10 No Prescaler */
+       {15, 100},      /* CHANNEL 11 */
+       {1, 4},         /* CHANNEL 12 */
+       {1, 1},         /* CHANNEL 13 Reserved channels */
+       {1, 1},         /* CHANNEL 14 Reseved channels */
+       {5, 11},        /* CHANNEL 15 */
+};
+
+
+/*
+ * Conversion table from -3 to 55 degree Celcius
+ */
+static int therm_tbl[] = {
+30800, 29500,  28300,  27100,
+26000, 24900,  23900,  22900,  22000,  21100,  20300,  19400,  18700,  17900,
+17200, 16500,  15900,  15300,  14700,  14100,  13600,  13100,  12600,  12100,
+11600, 11200,  10800,  10400,  10000,  9630,   9280,   8950,   8620,   8310,
+8020,  7730,   7460,   7200,   6950,   6710,   6470,   6250,   6040,   5830,
+5640,  5450,   5260,   5090,   4920,   4760,   4600,   4450,   4310,   4170,
+4040,  3910,   3790,   3670,   3550
+};
+
+/*
+ * Structure containing the registers
+ * of different conversion methods supported by MADC.
+ * Hardware or RT real time conversion request initiated by external host
+ * processor for RT Signal conversions.
+ * External host processors can also request for non RT conversions
+ * SW1 and SW2 software conversions also called asynchronous or GPC request.
+ */
+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,
+                             },
+};
+
+/*
+ * Function to read a particular channel value.
+ * @madc - pointer to struct twl4030_madc_data
+ * @reg - lsb of ADC Channel
+ * If the i2c read fails it returns an error else returns 0.
+ */
+static int twl4030_madc_channel_raw_read(struct twl4030_madc_data *madc, u8 reg)
+{
+       u8 msb, lsb;
+       int ret;
+       /*
+        * For each ADC channel, we have MSB and LSB register pair. MSB address
+        * is always LSB address+1. reg parameter is the address of LSB register
+        */
+       ret = twl_i2c_read_u8(TWL4030_MODULE_MADC, &msb, reg + 1);
+       if (ret) {
+               dev_err(madc->dev, "unable to read MSB register 0x%X\n",
+                       reg + 1);
+               return ret;
+       }
+       ret = twl_i2c_read_u8(TWL4030_MODULE_MADC, &lsb, reg);
+       if (ret) {
+               dev_err(madc->dev, "unable to read LSB register 0x%X\n", reg);
+               return ret;
+       }
+
+       return (int)(((msb << 8) | lsb) >> 6);
+}
+
+/*
+ * Return battery temperature
+ * Or < 0 on failure.
+ */
+static int twl4030battery_temperature(int raw_volt)
+{
+       u8 val;
+       int temp, curr, volt, res, ret;
+
+       volt = (raw_volt * TEMP_STEP_SIZE) / TEMP_PSR_R;
+       /* Getting and calculating the supply current in micro ampers */
+       ret = twl_i2c_read_u8(TWL4030_MODULE_MAIN_CHARGE, &val,
+               REG_BCICTL2);
+       if (ret < 0)
+               return ret;
+       curr = ((val & TWL4030_BCI_ITHEN) + 1) * 10;
+       /* Getting and calculating the thermistor resistance in ohms */
+       res = volt * 1000 / curr;
+       /* calculating temperature */
+       for (temp = 58; temp >= 0; temp--) {
+               int actual = therm_tbl[temp];
+
+               if ((actual - res) >= 0)
+                       break;
+       }
+
+       return temp + 1;
+}
+
+static int twl4030battery_current(int raw_volt)
+{
+       int ret;
+       u8 val;
+
+       ret = twl_i2c_read_u8(TWL4030_MODULE_MAIN_CHARGE, &val,
+               TWL4030_BCI_BCICTL1);
+       if (ret)
+               return ret;
+       if (val & TWL4030_BCI_CGAIN) /* slope of 0.44 mV/mA */
+               return (raw_volt * CURR_STEP_SIZE) / CURR_PSR_R1;
+       else /* slope of 0.88 mV/mA */
+               return (raw_volt * CURR_STEP_SIZE) / CURR_PSR_R2;
+}
+/*
+ * Function to read channel values
+ * @madc - pointer to twl4030_madc_data struct
+ * @reg_base - Base address of the first channel
+ * @Channels - 16 bit bitmap. If the bit is set, channel value is read
+ * @buf - The channel values are stored here. if read fails error
+ * value is stored
+ * Returns the number of successfully read channels.
+ */
+static int twl4030_madc_read_channels(struct twl4030_madc_data *madc,
+                                     u8 reg_base, unsigned
+                                               long channels, int *buf)
+{
+       int count = 0, count_req = 0, i;
+       u8 reg;
+
+       for_each_set_bit(i, &channels, TWL4030_MADC_MAX_CHANNELS) {
+               reg = reg_base + 2 * i;
+               buf[i] = twl4030_madc_channel_raw_read(madc, reg);
+               if (buf[i] < 0) {
+                       dev_err(madc->dev,
+                               "Unable to read register 0x%X\n", reg);
+                       count_req++;
+                       continue;
+               }
+               switch (i) {
+               case 10:
+                       buf[i] = twl4030battery_current(buf[i]);
+                       if (buf[i] < 0) {
+                               dev_err(madc->dev, "err reading current\n");
+                               count_req++;
+                       } else {
+                               count++;
+                               buf[i] = buf[i] - 750;
+                       }
+                       break;
+               case 1:
+                       buf[i] = twl4030battery_temperature(buf[i]);
+                       if (buf[i] < 0) {
+                               dev_err(madc->dev, "err reading temperature\n");
+                               count_req++;
+                       } else {
+                               buf[i] -= 3;
+                               count++;
+                       }
+                       break;
+               default:
+                       count++;
+                       /* Analog Input (V) = conv_result * step_size / R
+                        * conv_result = decimal value of 10-bit conversion
+                        *               result
+                        * step size = 1.5 / (2 ^ 10 -1)
+                        * R = Prescaler ratio for input channels.
+                        * Result given in mV hence multiplied by 1000.
+                        */
+                       buf[i] = (buf[i] * 3 * 1000 *
+                                twl4030_divider_ratios[i].denominator)
+                               / (2 * 1023 *
+                               twl4030_divider_ratios[i].numerator);
+               }
+       }
+       if (count_req)
+               dev_err(madc->dev, "%d channel conversion failed\n", count_req);
+
+       return count;
+}
+
+/*
+ * Enables irq.
+ * @madc - pointer to twl4030_madc_data struct
+ * @id - irq number to be enabled
+ * can take one of TWL4030_MADC_RT, TWL4030_MADC_SW1, TWL4030_MADC_SW2
+ * corresponding to RT, SW1, SW2 conversion requests.
+ * If the i2c read fails it returns an error else returns 0.
+ */
+static int twl4030_madc_enable_irq(struct twl4030_madc_data *madc, u8 id)
+{
+       u8 val;
+       int ret;
+
+       ret = twl_i2c_read_u8(TWL4030_MODULE_MADC, &val, madc->imr);
+       if (ret) {
+               dev_err(madc->dev, "unable to read imr register 0x%X\n",
+                       madc->imr);
+               return ret;
+       }
+       val &= ~(1 << id);
+       ret = twl_i2c_write_u8(TWL4030_MODULE_MADC, val, madc->imr);
+       if (ret) {
+               dev_err(madc->dev,
+                       "unable to write imr register 0x%X\n", madc->imr);
+               return ret;
+
+       }
+
+       return 0;
+}
+
+/*
+ * Disables irq.
+ * @madc - pointer to twl4030_madc_data struct
+ * @id - irq number to be disabled
+ * can take one of TWL4030_MADC_RT, TWL4030_MADC_SW1, TWL4030_MADC_SW2
+ * corresponding to RT, SW1, SW2 conversion requests.
+ * Returns error if i2c read/write fails.
+ */
+static int twl4030_madc_disable_irq(struct twl4030_madc_data *madc, u8 id)
+{
+       u8 val;
+       int ret;
+
+       ret = twl_i2c_read_u8(TWL4030_MODULE_MADC, &val, madc->imr);
+       if (ret) {
+               dev_err(madc->dev, "unable to read imr register 0x%X\n",
+                       madc->imr);
+               return ret;
+       }
+       val |= (1 << id);
+       ret = twl_i2c_write_u8(TWL4030_MODULE_MADC, val, madc->imr);
+       if (ret) {
+               dev_err(madc->dev,
+                       "unable to write imr register 0x%X\n", madc->imr);
+               return ret;
+       }
+
+       return 0;
+}
+
+static irqreturn_t twl4030_madc_threaded_irq_handler(int irq, void *_madc)
+{
+       struct twl4030_madc_data *madc = _madc;
+       const struct twl4030_madc_conversion_method *method;
+       u8 isr_val, imr_val;
+       int i, len, ret;
+       struct twl4030_madc_request *r;
+
+       mutex_lock(&madc->lock);
+       ret = twl_i2c_read_u8(TWL4030_MODULE_MADC, &isr_val, madc->isr);
+       if (ret) {
+               dev_err(madc->dev, "unable to read isr register 0x%X\n",
+                       madc->isr);
+               goto err_i2c;
+       }
+       ret = twl_i2c_read_u8(TWL4030_MODULE_MADC, &imr_val, madc->imr);
+       if (ret) {
+               dev_err(madc->dev, "unable to read imr register 0x%X\n",
+                       madc->imr);
+               goto err_i2c;
+       }
+       isr_val &= ~imr_val;
+       for (i = 0; i < TWL4030_MADC_NUM_METHODS; i++) {
+               if (!(isr_val & (1 << i)))
+                       continue;
+               ret = twl4030_madc_disable_irq(madc, i);
+               if (ret < 0)
+                       dev_dbg(madc->dev, "Disable interrupt failed%d\n", i);
+               madc->requests[i].result_pending = 1;
+       }
+       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);
+
+       return IRQ_HANDLED;
+
+err_i2c:
+       /*
+        * In case of error check whichever request is active
+        * and service the same.
+        */
+       for (i = 0; i < TWL4030_MADC_NUM_METHODS; i++) {
+               r = &madc->requests[i];
+               if (r->active == 0)
+                       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);
+
+       return IRQ_HANDLED;
+}
+
+static int twl4030_madc_set_irq(struct twl4030_madc_data *madc,
+                               struct twl4030_madc_request *req)
+{
+       struct twl4030_madc_request *p;
+       int ret;
+
+       p = &madc->requests[req->method];
+       memcpy(p, req, sizeof(*req));
+       ret = twl4030_madc_enable_irq(madc, req->method);
+       if (ret < 0) {
+               dev_err(madc->dev, "enable irq failed!!\n");
+               return ret;
+       }
+
+       return 0;
+}
+
+/*
+ * Function which enables the madc conversion
+ * by writing to the control register.
+ * @madc - pointer to twl4030_madc_data struct
+ * @conv_method - can be TWL4030_MADC_RT, TWL4030_MADC_SW2, TWL4030_MADC_SW1
+ * corresponding to RT SW1 or SW2 conversion methods.
+ * Returns 0 if succeeds else a negative error value
+ */
+static int twl4030_madc_start_conversion(struct twl4030_madc_data *madc,
+                                        int conv_method)
+{
+       const struct twl4030_madc_conversion_method *method;
+       int ret = 0;
+       method = &twl4030_conversion_methods[conv_method];
+       switch (conv_method) {
+       case TWL4030_MADC_SW1:
+       case TWL4030_MADC_SW2:
+               ret = twl_i2c_write_u8(TWL4030_MODULE_MADC,
+                                      TWL4030_MADC_SW_START, method->ctrl);
+               if (ret) {
+                       dev_err(madc->dev,
+                               "unable to write ctrl register 0x%X\n",
+                               method->ctrl);
+                       return ret;
+               }
+               break;
+       default:
+               break;
+       }
+
+       return 0;
+}
+
+/*
+ * Function that waits for conversion to be ready
+ * @madc - pointer to twl4030_madc_data struct
+ * @timeout_ms - timeout value in milliseconds
+ * @status_reg - ctrl register
+ * returns 0 if succeeds else a negative error value
+ */
+static int twl4030_madc_wait_conversion_ready(struct twl4030_madc_data *madc,
+                                             unsigned int timeout_ms,
+                                             u8 status_reg)
+{
+       unsigned long timeout;
+       int ret;
+
+       timeout = jiffies + msecs_to_jiffies(timeout_ms);
+       do {
+               u8 reg;
+
+               ret = twl_i2c_read_u8(TWL4030_MODULE_MADC, &reg, status_reg);
+               if (ret) {
+                       dev_err(madc->dev,
+                               "unable to read status register 0x%X\n",
+                               status_reg);
+                       return ret;
+               }
+               if (!(reg & TWL4030_MADC_BUSY) && (reg & TWL4030_MADC_EOC_SW))
+                       return 0;
+               usleep_range(500, 2000);
+       } while (!time_after(jiffies, timeout));
+       dev_err(madc->dev, "conversion timeout!\n");
+
+       return -EAGAIN;
+}
+
+/*
+ * An exported function which can be called from other kernel drivers.
+ * @req twl4030_madc_request structure
+ * req->rbuf will be filled with read values of channels based on the
+ * channel index. If a particular channel reading fails there will
+ * be a negative error value in the corresponding array element.
+ * returns 0 if succeeds else error value
+ */
+int twl4030_madc_conversion(struct twl4030_madc_request *req)
+{
+       const struct twl4030_madc_conversion_method *method;
+       u8 ch_msb, ch_lsb;
+       int ret;
+
+       if (!req)
+               return -EINVAL;
+       mutex_lock(&twl4030_madc->lock);
+       if (req->method < TWL4030_MADC_RT || req->method > TWL4030_MADC_SW2) {
+               ret = -EINVAL;
+               goto out;
+       }
+       /* Do we have a conversion request ongoing */
+       if (twl4030_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 */
+       ret = twl_i2c_write_u8(TWL4030_MODULE_MADC, ch_msb, method->sel + 1);
+       if (ret) {
+               dev_err(twl4030_madc->dev,
+                       "unable to write sel register 0x%X\n", method->sel + 1);
+               return ret;
+       }
+       ret = twl_i2c_write_u8(TWL4030_MODULE_MADC, ch_lsb, method->sel);
+       if (ret) {
+               dev_err(twl4030_madc->dev,
+                       "unable to write sel register 0x%X\n", method->sel + 1);
+               return ret;
+       }
+       /* Select averaging for all channels if do_avg is set */
+       if (req->do_avg) {
+               ret = twl_i2c_write_u8(TWL4030_MODULE_MADC,
+                                      ch_msb, method->avg + 1);
+               if (ret) {
+                       dev_err(twl4030_madc->dev,
+                               "unable to write avg register 0x%X\n",
+                               method->avg + 1);
+                       return ret;
+               }
+               ret = twl_i2c_write_u8(TWL4030_MODULE_MADC,
+                                      ch_lsb, method->avg);
+               if (ret) {
+                       dev_err(twl4030_madc->dev,
+                               "unable to write sel reg 0x%X\n",
+                               method->sel + 1);
+                       return ret;
+               }
+       }
+       if (req->type == TWL4030_MADC_IRQ_ONESHOT && req->func_cb != NULL) {
+               ret = twl4030_madc_set_irq(twl4030_madc, req);
+               if (ret < 0)
+                       goto out;
+               ret = twl4030_madc_start_conversion(twl4030_madc, req->method);
+               if (ret < 0)
+                       goto out;
+               twl4030_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;
+       }
+       ret = twl4030_madc_start_conversion(twl4030_madc, req->method);
+       if (ret < 0)
+               goto out;
+       twl4030_madc->requests[req->method].active = 1;
+       /* Wait until conversion is ready (ctrl register returns EOC) */
+       ret = twl4030_madc_wait_conversion_ready(twl4030_madc, 5, method->ctrl);
+       if (ret) {
+               twl4030_madc->requests[req->method].active = 0;
+               goto out;
+       }
+       ret = twl4030_madc_read_channels(twl4030_madc, method->rbase,
+                                        req->channels, req->rbuf);
+       twl4030_madc->requests[req->method].active = 0;
+
+out:
+       mutex_unlock(&twl4030_madc->lock);
+
+       return ret;
+}
+EXPORT_SYMBOL_GPL(twl4030_madc_conversion);
+
+/*
+ * Return channel value
+ * Or < 0 on failure.
+ */
+int twl4030_get_madc_conversion(int channel_no)
+{
+       struct twl4030_madc_request req;
+       int temp = 0;
+       int ret;
+
+       req.channels = (1 << channel_no);
+       req.method = TWL4030_MADC_SW2;
+       req.active = 0;
+       req.func_cb = NULL;
+       ret = twl4030_madc_conversion(&req);
+       if (ret < 0)
+               return ret;
+       if (req.rbuf[channel_no] > 0)
+               temp = req.rbuf[channel_no];
+
+       return temp;
+}
+EXPORT_SYMBOL_GPL(twl4030_get_madc_conversion);
+
+/*
+ * Function to enable or disable bias current for
+ * main battery type reading or temperature sensing
+ * @madc - pointer to twl4030_madc_data struct
+ * @chan - can be one of the two values
+ * TWL4030_BCI_ITHEN - Enables bias current for main battery type reading
+ * TWL4030_BCI_TYPEN - Enables bias current for main battery temperature
+ * sensing
+ * @on - enable or disable chan.
+ */
+static int twl4030_madc_set_current_generator(struct twl4030_madc_data *madc,
+                                             int chan, int on)
+{
+       int ret;
+       u8 regval;
+
+       ret = twl_i2c_read_u8(TWL4030_MODULE_MAIN_CHARGE,
+                             &regval, TWL4030_BCI_BCICTL1);
+       if (ret) {
+               dev_err(madc->dev, "unable to read BCICTL1 reg 0x%X",
+                       TWL4030_BCI_BCICTL1);
+               return ret;
+       }
+       if (on)
+               regval |= chan ? TWL4030_BCI_ITHEN : TWL4030_BCI_TYPEN;
+       else
+               regval &= chan ? ~TWL4030_BCI_ITHEN : ~TWL4030_BCI_TYPEN;
+       ret = twl_i2c_write_u8(TWL4030_MODULE_MAIN_CHARGE,
+                              regval, TWL4030_BCI_BCICTL1);
+       if (ret) {
+               dev_err(madc->dev, "unable to write BCICTL1 reg 0x%X\n",
+                       TWL4030_BCI_BCICTL1);
+               return ret;
+       }
+
+       return 0;
+}
+
+/*
+ * Function that sets MADC software power on bit to enable MADC
+ * @madc - pointer to twl4030_madc_data struct
+ * @on - Enable or disable MADC software powen on bit.
+ * returns error if i2c read/write fails else 0
+ */
+static int twl4030_madc_set_power(struct twl4030_madc_data *madc, int on)
+{
+       u8 regval;
+       int ret;
+
+       ret = twl_i2c_read_u8(TWL4030_MODULE_MAIN_CHARGE,
+                             &regval, TWL4030_MADC_CTRL1);
+       if (ret) {
+               dev_err(madc->dev, "unable to read madc ctrl1 reg 0x%X\n",
+                       TWL4030_MADC_CTRL1);
+               return ret;
+       }
+       if (on)
+               regval |= TWL4030_MADC_MADCON;
+       else
+               regval &= ~TWL4030_MADC_MADCON;
+       ret = twl_i2c_write_u8(TWL4030_MODULE_MADC, regval, TWL4030_MADC_CTRL1);
+       if (ret) {
+               dev_err(madc->dev, "unable to write madc ctrl1 reg 0x%X\n",
+                       TWL4030_MADC_CTRL1);
+               return ret;
+       }
+
+       return 0;
+}
+
+/*
+ * Initialize MADC and request for threaded irq
+ */
+static int __devinit 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;
+
+       if (!pdata) {
+               dev_err(&pdev->dev, "platform_data not available\n");
+               return -EINVAL;
+       }
+       madc = kzalloc(sizeof(*madc), GFP_KERNEL);
+       if (!madc)
+               return -ENOMEM;
+
+       /*
+        * Phoenix provides 2 interrupt lines. The first one is connected to
+        * the OMAP. The other one can be connected to the other processor such
+        * as modem. Hence two separate ISR and IMR registers.
+        */
+       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 = twl4030_madc_set_power(madc, 1);
+       if (ret < 0)
+               goto err_power;
+       ret = twl4030_madc_set_current_generator(madc, 0, 1);
+       if (ret < 0)
+               goto err_current_generator;
+
+       ret = twl_i2c_read_u8(TWL4030_MODULE_MAIN_CHARGE,
+                             &regval, TWL4030_BCI_BCICTL1);
+       if (ret) {
+               dev_err(&pdev->dev, "unable to read reg BCI CTL1 0x%X\n",
+                       TWL4030_BCI_BCICTL1);
+               goto err_i2c;
+       }
+       regval |= TWL4030_BCI_MESBAT;
+       ret = twl_i2c_write_u8(TWL4030_MODULE_MAIN_CHARGE,
+                              regval, TWL4030_BCI_BCICTL1);
+       if (ret) {
+               dev_err(&pdev->dev, "unable to write reg BCI Ctl1 0x%X\n",
+                       TWL4030_BCI_BCICTL1);
+               goto err_i2c;
+       }
+       platform_set_drvdata(pdev, madc);
+       mutex_init(&madc->lock);
+       ret = request_threaded_irq(platform_get_irq(pdev, 0), NULL,
+                                  twl4030_madc_threaded_irq_handler,
+                                  IRQF_TRIGGER_RISING, "twl4030_madc", madc);
+       if (ret) {
+               dev_dbg(&pdev->dev, "could not request irq\n");
+               goto err_irq;
+       }
+       twl4030_madc = madc;
+       return 0;
+err_irq:
+       platform_set_drvdata(pdev, NULL);
+err_i2c:
+       twl4030_madc_set_current_generator(madc, 0, 0);
+err_current_generator:
+       twl4030_madc_set_power(madc, 0);
+err_power:
+       kfree(madc);
+
+       return ret;
+}
+
+static int __devexit twl4030_madc_remove(struct platform_device *pdev)
+{
+       struct twl4030_madc_data *madc = platform_get_drvdata(pdev);
+
+       free_irq(platform_get_irq(pdev, 0), madc);
+       platform_set_drvdata(pdev, NULL);
+       twl4030_madc_set_current_generator(madc, 0, 0);
+       twl4030_madc_set_power(madc, 0);
+       kfree(madc);
+
+       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_DESCRIPTION("TWL4030 ADC driver");
+MODULE_LICENSE("GPL");
+MODULE_AUTHOR("J Keerthy");
+MODULE_ALIAS("twl4030_madc");
diff --git a/include/linux/i2c/twl4030-madc.h b/include/linux/i2c/twl4030-madc.h
new file mode 100644 (file)
index 0000000..6427d29
--- /dev/null
@@ -0,0 +1,141 @@
+/*
+ * twl4030_madc.h - Header for TWL4030 MADC
+ *
+ * Copyright (C) 2011 Texas Instruments Incorporated - http://www.ti.com/
+ * J Keerthy <j-keerthy@ti.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
+ *
+ */
+
+#ifndef _TWL4030_MADC_H
+#define _TWL4030_MADC_H
+
+struct twl4030_madc_conversion_method {
+       u8 sel;
+       u8 avg;
+       u8 rbase;
+       u8 ctrl;
+};
+
+#define TWL4030_MADC_MAX_CHANNELS 16
+
+
+/*
+ * twl4030_madc_request- madc request packet for channel conversion
+ * @channels:  16 bit bitmap for individual channels
+ * @do_avgP:   sample the input channel for 4 consecutive cycles
+ * @method:    RT, SW1, SW2
+ * @type:      Polling or interrupt based method
+ */
+
+struct twl4030_madc_request {
+       unsigned long channels;
+       u16 do_avg;
+       u16 method;
+       u16 type;
+       bool active;
+       bool result_pending;
+       int rbuf[TWL4030_MADC_MAX_CHANNELS];
+       void (*func_cb)(int len, int channels, int *buf);
+};
+
+enum conversion_methods {
+       TWL4030_MADC_RT,
+       TWL4030_MADC_SW1,
+       TWL4030_MADC_SW2,
+       TWL4030_MADC_NUM_METHODS
+};
+
+enum sample_type {
+       TWL4030_MADC_WAIT,
+       TWL4030_MADC_IRQ_ONESHOT,
+       TWL4030_MADC_IRQ_REARM
+};
+
+#define TWL4030_MADC_CTRL1             0x00
+#define TWL4030_MADC_CTRL2             0x01
+
+#define TWL4030_MADC_RTSELECT_LSB      0x02
+#define TWL4030_MADC_SW1SELECT_LSB     0x06
+#define TWL4030_MADC_SW2SELECT_LSB     0x0A
+
+#define TWL4030_MADC_RTAVERAGE_LSB     0x04
+#define TWL4030_MADC_SW1AVERAGE_LSB    0x08
+#define TWL4030_MADC_SW2AVERAGE_LSB    0x0C
+
+#define TWL4030_MADC_CTRL_SW1          0x12
+#define TWL4030_MADC_CTRL_SW2          0x13
+
+#define TWL4030_MADC_RTCH0_LSB         0x17
+#define TWL4030_MADC_GPCH0_LSB         0x37
+
+#define TWL4030_MADC_MADCON    (1 << 0)        /* MADC power on */
+#define TWL4030_MADC_BUSY      (1 << 0)        /* MADC busy */
+/* MADC conversion completion */
+#define TWL4030_MADC_EOC_SW    (1 << 1)
+/* MADC SWx start conversion */
+#define TWL4030_MADC_SW_START  (1 << 5)
+#define TWL4030_MADC_ADCIN0    (1 << 0)
+#define TWL4030_MADC_ADCIN1    (1 << 1)
+#define TWL4030_MADC_ADCIN2    (1 << 2)
+#define TWL4030_MADC_ADCIN3    (1 << 3)
+#define TWL4030_MADC_ADCIN4    (1 << 4)
+#define TWL4030_MADC_ADCIN5    (1 << 5)
+#define TWL4030_MADC_ADCIN6    (1 << 6)
+#define TWL4030_MADC_ADCIN7    (1 << 7)
+#define TWL4030_MADC_ADCIN8    (1 << 8)
+#define TWL4030_MADC_ADCIN9    (1 << 9)
+#define TWL4030_MADC_ADCIN10   (1 << 10)
+#define TWL4030_MADC_ADCIN11   (1 << 11)
+#define TWL4030_MADC_ADCIN12   (1 << 12)
+#define TWL4030_MADC_ADCIN13   (1 << 13)
+#define TWL4030_MADC_ADCIN14   (1 << 14)
+#define TWL4030_MADC_ADCIN15   (1 << 15)
+
+/* Fixed channels */
+#define TWL4030_MADC_BTEMP     TWL4030_MADC_ADCIN1
+#define TWL4030_MADC_VBUS      TWL4030_MADC_ADCIN8
+#define TWL4030_MADC_VBKB      TWL4030_MADC_ADCIN9
+#define TWL4030_MADC_ICHG      TWL4030_MADC_ADCIN10
+#define TWL4030_MADC_VCHG      TWL4030_MADC_ADCIN11
+#define TWL4030_MADC_VBAT      TWL4030_MADC_ADCIN12
+
+/* Step size and prescaler ratio */
+#define TEMP_STEP_SIZE          147
+#define TEMP_PSR_R              100
+#define CURR_STEP_SIZE         147
+#define CURR_PSR_R1            44
+#define CURR_PSR_R2            88
+
+#define TWL4030_BCI_BCICTL1    0x23
+#define TWL4030_BCI_CGAIN      0x020
+#define TWL4030_BCI_MESBAT     (1 << 1)
+#define TWL4030_BCI_TYPEN      (1 << 4)
+#define TWL4030_BCI_ITHEN      (1 << 3)
+
+#define REG_BCICTL2             0x024
+#define TWL4030_BCI_ITHSENS    0x007
+
+struct twl4030_madc_user_parms {
+       int channel;
+       int average;
+       int status;
+       u16 result;
+};
+
+int twl4030_madc_conversion(struct twl4030_madc_request *conv);
+int twl4030_get_madc_conversion(int channel_no);
+#endif