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-rw-r--r--drivers/thermal/ti-soc-thermal/ti-bandgap.c1267
1 files changed, 1267 insertions, 0 deletions
diff --git a/drivers/thermal/ti-soc-thermal/ti-bandgap.c b/drivers/thermal/ti-soc-thermal/ti-bandgap.c
new file mode 100644
index 000000000..097328d8e
--- /dev/null
+++ b/drivers/thermal/ti-soc-thermal/ti-bandgap.c
@@ -0,0 +1,1267 @@
+/*
+ * TI Bandgap temperature sensor driver
+ *
+ * Copyright (C) 2011-2012 Texas Instruments Incorporated - http://www.ti.com/
+ * Author: J Keerthy <j-keerthy@ti.com>
+ * Author: Moiz Sonasath <m-sonasath@ti.com>
+ * Couple of fixes, DT and MFD adaptation:
+ * Eduardo Valentin <eduardo.valentin@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
+ *
+ */
+
+#include <linux/module.h>
+#include <linux/export.h>
+#include <linux/init.h>
+#include <linux/kernel.h>
+#include <linux/interrupt.h>
+#include <linux/clk.h>
+#include <linux/gpio.h>
+#include <linux/platform_device.h>
+#include <linux/err.h>
+#include <linux/types.h>
+#include <linux/spinlock.h>
+#include <linux/reboot.h>
+#include <linux/of_device.h>
+#include <linux/of_platform.h>
+#include <linux/of_irq.h>
+#include <linux/of_gpio.h>
+#include <linux/io.h>
+
+#include "ti-bandgap.h"
+
+static int ti_bandgap_force_single_read(struct ti_bandgap *bgp, int id);
+
+/*** Helper functions to access registers and their bitfields ***/
+
+/**
+ * ti_bandgap_readl() - simple read helper function
+ * @bgp: pointer to ti_bandgap structure
+ * @reg: desired register (offset) to be read
+ *
+ * Helper function to read bandgap registers. It uses the io remapped area.
+ * Return: the register value.
+ */
+static u32 ti_bandgap_readl(struct ti_bandgap *bgp, u32 reg)
+{
+ return readl(bgp->base + reg);
+}
+
+/**
+ * ti_bandgap_writel() - simple write helper function
+ * @bgp: pointer to ti_bandgap structure
+ * @val: desired register value to be written
+ * @reg: desired register (offset) to be written
+ *
+ * Helper function to write bandgap registers. It uses the io remapped area.
+ */
+static void ti_bandgap_writel(struct ti_bandgap *bgp, u32 val, u32 reg)
+{
+ writel(val, bgp->base + reg);
+}
+
+/**
+ * DOC: macro to update bits.
+ *
+ * RMW_BITS() - used to read, modify and update bandgap bitfields.
+ * The value passed will be shifted.
+ */
+#define RMW_BITS(bgp, id, reg, mask, val) \
+do { \
+ struct temp_sensor_registers *t; \
+ u32 r; \
+ \
+ t = bgp->conf->sensors[(id)].registers; \
+ r = ti_bandgap_readl(bgp, t->reg); \
+ r &= ~t->mask; \
+ r |= (val) << __ffs(t->mask); \
+ ti_bandgap_writel(bgp, r, t->reg); \
+} while (0)
+
+/*** Basic helper functions ***/
+
+/**
+ * ti_bandgap_power() - controls the power state of a bandgap device
+ * @bgp: pointer to ti_bandgap structure
+ * @on: desired power state (1 - on, 0 - off)
+ *
+ * Used to power on/off a bandgap device instance. Only used on those
+ * that features tempsoff bit.
+ *
+ * Return: 0 on success, -ENOTSUPP if tempsoff is not supported.
+ */
+static int ti_bandgap_power(struct ti_bandgap *bgp, bool on)
+{
+ int i;
+
+ if (!TI_BANDGAP_HAS(bgp, POWER_SWITCH))
+ return -ENOTSUPP;
+
+ for (i = 0; i < bgp->conf->sensor_count; i++)
+ /* active on 0 */
+ RMW_BITS(bgp, i, temp_sensor_ctrl, bgap_tempsoff_mask, !on);
+ return 0;
+}
+
+/**
+ * ti_errata814_bandgap_read_temp() - helper function to read dra7 sensor temperature
+ * @bgp: pointer to ti_bandgap structure
+ * @reg: desired register (offset) to be read
+ *
+ * Function to read dra7 bandgap sensor temperature. This is done separately
+ * so as to workaround the errata "Bandgap Temperature read Dtemp can be
+ * corrupted" - Errata ID: i814".
+ * Read accesses to registers listed below can be corrupted due to incorrect
+ * resynchronization between clock domains.
+ * Read access to registers below can be corrupted :
+ * CTRL_CORE_DTEMP_MPU/GPU/CORE/DSPEVE/IVA_n (n = 0 to 4)
+ * CTRL_CORE_TEMP_SENSOR_MPU/GPU/CORE/DSPEVE/IVA_n
+ *
+ * Return: the register value.
+ */
+static u32 ti_errata814_bandgap_read_temp(struct ti_bandgap *bgp, u32 reg)
+{
+ u32 val1, val2;
+
+ val1 = ti_bandgap_readl(bgp, reg);
+ val2 = ti_bandgap_readl(bgp, reg);
+
+ /* If both times we read the same value then that is right */
+ if (val1 == val2)
+ return val1;
+
+ /* if val1 and val2 are different read it third time */
+ return ti_bandgap_readl(bgp, reg);
+}
+
+/**
+ * ti_bandgap_read_temp() - helper function to read sensor temperature
+ * @bgp: pointer to ti_bandgap structure
+ * @id: bandgap sensor id
+ *
+ * Function to concentrate the steps to read sensor temperature register.
+ * This function is desired because, depending on bandgap device version,
+ * it might be needed to freeze the bandgap state machine, before fetching
+ * the register value.
+ *
+ * Return: temperature in ADC values.
+ */
+static u32 ti_bandgap_read_temp(struct ti_bandgap *bgp, int id)
+{
+ struct temp_sensor_registers *tsr;
+ u32 temp, reg;
+
+ tsr = bgp->conf->sensors[id].registers;
+ reg = tsr->temp_sensor_ctrl;
+
+ if (TI_BANDGAP_HAS(bgp, FREEZE_BIT)) {
+ RMW_BITS(bgp, id, bgap_mask_ctrl, mask_freeze_mask, 1);
+ /*
+ * In case we cannot read from cur_dtemp / dtemp_0,
+ * then we read from the last valid temp read
+ */
+ reg = tsr->ctrl_dtemp_1;
+ }
+
+ /* read temperature */
+ if (TI_BANDGAP_HAS(bgp, ERRATA_814))
+ temp = ti_errata814_bandgap_read_temp(bgp, reg);
+ else
+ temp = ti_bandgap_readl(bgp, reg);
+
+ temp &= tsr->bgap_dtemp_mask;
+
+ if (TI_BANDGAP_HAS(bgp, FREEZE_BIT))
+ RMW_BITS(bgp, id, bgap_mask_ctrl, mask_freeze_mask, 0);
+
+ return temp;
+}
+
+/*** IRQ handlers ***/
+
+/**
+ * ti_bandgap_talert_irq_handler() - handles Temperature alert IRQs
+ * @irq: IRQ number
+ * @data: private data (struct ti_bandgap *)
+ *
+ * This is the Talert handler. Use it only if bandgap device features
+ * HAS(TALERT). This handler goes over all sensors and checks their
+ * conditions and acts accordingly. In case there are events pending,
+ * it will reset the event mask to wait for the opposite event (next event).
+ * Every time there is a new event, it will be reported to thermal layer.
+ *
+ * Return: IRQ_HANDLED
+ */
+static irqreturn_t ti_bandgap_talert_irq_handler(int irq, void *data)
+{
+ struct ti_bandgap *bgp = data;
+ struct temp_sensor_registers *tsr;
+ u32 t_hot = 0, t_cold = 0, ctrl;
+ int i;
+
+ spin_lock(&bgp->lock);
+ for (i = 0; i < bgp->conf->sensor_count; i++) {
+ tsr = bgp->conf->sensors[i].registers;
+ ctrl = ti_bandgap_readl(bgp, tsr->bgap_status);
+
+ /* Read the status of t_hot */
+ t_hot = ctrl & tsr->status_hot_mask;
+
+ /* Read the status of t_cold */
+ t_cold = ctrl & tsr->status_cold_mask;
+
+ if (!t_cold && !t_hot)
+ continue;
+
+ ctrl = ti_bandgap_readl(bgp, tsr->bgap_mask_ctrl);
+ /*
+ * One TALERT interrupt: Two sources
+ * If the interrupt is due to t_hot then mask t_hot and
+ * and unmask t_cold else mask t_cold and unmask t_hot
+ */
+ if (t_hot) {
+ ctrl &= ~tsr->mask_hot_mask;
+ ctrl |= tsr->mask_cold_mask;
+ } else if (t_cold) {
+ ctrl &= ~tsr->mask_cold_mask;
+ ctrl |= tsr->mask_hot_mask;
+ }
+
+ ti_bandgap_writel(bgp, ctrl, tsr->bgap_mask_ctrl);
+
+ dev_dbg(bgp->dev,
+ "%s: IRQ from %s sensor: hotevent %d coldevent %d\n",
+ __func__, bgp->conf->sensors[i].domain,
+ t_hot, t_cold);
+
+ /* report temperature to whom may concern */
+ if (bgp->conf->report_temperature)
+ bgp->conf->report_temperature(bgp, i);
+ }
+ spin_unlock(&bgp->lock);
+
+ return IRQ_HANDLED;
+}
+
+/**
+ * ti_bandgap_tshut_irq_handler() - handles Temperature shutdown signal
+ * @irq: IRQ number
+ * @data: private data (unused)
+ *
+ * This is the Tshut handler. Use it only if bandgap device features
+ * HAS(TSHUT). If any sensor fires the Tshut signal, we simply shutdown
+ * the system.
+ *
+ * Return: IRQ_HANDLED
+ */
+static irqreturn_t ti_bandgap_tshut_irq_handler(int irq, void *data)
+{
+ pr_emerg("%s: TSHUT temperature reached. Needs shut down...\n",
+ __func__);
+
+ orderly_poweroff(true);
+
+ return IRQ_HANDLED;
+}
+
+/*** Helper functions which manipulate conversion ADC <-> mi Celsius ***/
+
+/**
+ * ti_bandgap_adc_to_mcelsius() - converts an ADC value to mCelsius scale
+ * @bgp: struct ti_bandgap pointer
+ * @adc_val: value in ADC representation
+ * @t: address where to write the resulting temperature in mCelsius
+ *
+ * Simple conversion from ADC representation to mCelsius. In case the ADC value
+ * is out of the ADC conv table range, it returns -ERANGE, 0 on success.
+ * The conversion table is indexed by the ADC values.
+ *
+ * Return: 0 if conversion was successful, else -ERANGE in case the @adc_val
+ * argument is out of the ADC conv table range.
+ */
+static
+int ti_bandgap_adc_to_mcelsius(struct ti_bandgap *bgp, int adc_val, int *t)
+{
+ const struct ti_bandgap_data *conf = bgp->conf;
+
+ /* look up for temperature in the table and return the temperature */
+ if (adc_val < conf->adc_start_val || adc_val > conf->adc_end_val)
+ return -ERANGE;
+
+ *t = bgp->conf->conv_table[adc_val - conf->adc_start_val];
+ return 0;
+}
+
+/**
+ * ti_bandgap_validate() - helper to check the sanity of a struct ti_bandgap
+ * @bgp: struct ti_bandgap pointer
+ * @id: bandgap sensor id
+ *
+ * Checks if the bandgap pointer is valid and if the sensor id is also
+ * applicable.
+ *
+ * Return: 0 if no errors, -EINVAL for invalid @bgp pointer or -ERANGE if
+ * @id cannot index @bgp sensors.
+ */
+static inline int ti_bandgap_validate(struct ti_bandgap *bgp, int id)
+{
+ if (!bgp || IS_ERR(bgp)) {
+ pr_err("%s: invalid bandgap pointer\n", __func__);
+ return -EINVAL;
+ }
+
+ if ((id < 0) || (id >= bgp->conf->sensor_count)) {
+ dev_err(bgp->dev, "%s: sensor id out of range (%d)\n",
+ __func__, id);
+ return -ERANGE;
+ }
+
+ return 0;
+}
+
+/**
+ * ti_bandgap_read_counter() - read the sensor counter
+ * @bgp: pointer to bandgap instance
+ * @id: sensor id
+ * @interval: resulting update interval in miliseconds
+ */
+static void ti_bandgap_read_counter(struct ti_bandgap *bgp, int id,
+ int *interval)
+{
+ struct temp_sensor_registers *tsr;
+ int time;
+
+ tsr = bgp->conf->sensors[id].registers;
+ time = ti_bandgap_readl(bgp, tsr->bgap_counter);
+ time = (time & tsr->counter_mask) >>
+ __ffs(tsr->counter_mask);
+ time = time * 1000 / bgp->clk_rate;
+ *interval = time;
+}
+
+/**
+ * ti_bandgap_read_counter_delay() - read the sensor counter delay
+ * @bgp: pointer to bandgap instance
+ * @id: sensor id
+ * @interval: resulting update interval in miliseconds
+ */
+static void ti_bandgap_read_counter_delay(struct ti_bandgap *bgp, int id,
+ int *interval)
+{
+ struct temp_sensor_registers *tsr;
+ int reg_val;
+
+ tsr = bgp->conf->sensors[id].registers;
+
+ reg_val = ti_bandgap_readl(bgp, tsr->bgap_mask_ctrl);
+ reg_val = (reg_val & tsr->mask_counter_delay_mask) >>
+ __ffs(tsr->mask_counter_delay_mask);
+ switch (reg_val) {
+ case 0:
+ *interval = 0;
+ break;
+ case 1:
+ *interval = 1;
+ break;
+ case 2:
+ *interval = 10;
+ break;
+ case 3:
+ *interval = 100;
+ break;
+ case 4:
+ *interval = 250;
+ break;
+ case 5:
+ *interval = 500;
+ break;
+ default:
+ dev_warn(bgp->dev, "Wrong counter delay value read from register %X",
+ reg_val);
+ }
+}
+
+/**
+ * ti_bandgap_read_update_interval() - read the sensor update interval
+ * @bgp: pointer to bandgap instance
+ * @id: sensor id
+ * @interval: resulting update interval in miliseconds
+ *
+ * Return: 0 on success or the proper error code
+ */
+int ti_bandgap_read_update_interval(struct ti_bandgap *bgp, int id,
+ int *interval)
+{
+ int ret = 0;
+
+ ret = ti_bandgap_validate(bgp, id);
+ if (ret)
+ goto exit;
+
+ if (!TI_BANDGAP_HAS(bgp, COUNTER) &&
+ !TI_BANDGAP_HAS(bgp, COUNTER_DELAY)) {
+ ret = -ENOTSUPP;
+ goto exit;
+ }
+
+ if (TI_BANDGAP_HAS(bgp, COUNTER)) {
+ ti_bandgap_read_counter(bgp, id, interval);
+ goto exit;
+ }
+
+ ti_bandgap_read_counter_delay(bgp, id, interval);
+exit:
+ return ret;
+}
+
+/**
+ * ti_bandgap_write_counter_delay() - set the counter_delay
+ * @bgp: pointer to bandgap instance
+ * @id: sensor id
+ * @interval: desired update interval in miliseconds
+ *
+ * Return: 0 on success or the proper error code
+ */
+static int ti_bandgap_write_counter_delay(struct ti_bandgap *bgp, int id,
+ u32 interval)
+{
+ int rval;
+
+ switch (interval) {
+ case 0: /* Immediate conversion */
+ rval = 0x0;
+ break;
+ case 1: /* Conversion after ever 1ms */
+ rval = 0x1;
+ break;
+ case 10: /* Conversion after ever 10ms */
+ rval = 0x2;
+ break;
+ case 100: /* Conversion after ever 100ms */
+ rval = 0x3;
+ break;
+ case 250: /* Conversion after ever 250ms */
+ rval = 0x4;
+ break;
+ case 500: /* Conversion after ever 500ms */
+ rval = 0x5;
+ break;
+ default:
+ dev_warn(bgp->dev, "Delay %d ms is not supported\n", interval);
+ return -EINVAL;
+ }
+
+ spin_lock(&bgp->lock);
+ RMW_BITS(bgp, id, bgap_mask_ctrl, mask_counter_delay_mask, rval);
+ spin_unlock(&bgp->lock);
+
+ return 0;
+}
+
+/**
+ * ti_bandgap_write_counter() - set the bandgap sensor counter
+ * @bgp: pointer to bandgap instance
+ * @id: sensor id
+ * @interval: desired update interval in miliseconds
+ */
+static void ti_bandgap_write_counter(struct ti_bandgap *bgp, int id,
+ u32 interval)
+{
+ interval = interval * bgp->clk_rate / 1000;
+ spin_lock(&bgp->lock);
+ RMW_BITS(bgp, id, bgap_counter, counter_mask, interval);
+ spin_unlock(&bgp->lock);
+}
+
+/**
+ * ti_bandgap_write_update_interval() - set the update interval
+ * @bgp: pointer to bandgap instance
+ * @id: sensor id
+ * @interval: desired update interval in miliseconds
+ *
+ * Return: 0 on success or the proper error code
+ */
+int ti_bandgap_write_update_interval(struct ti_bandgap *bgp,
+ int id, u32 interval)
+{
+ int ret = ti_bandgap_validate(bgp, id);
+ if (ret)
+ goto exit;
+
+ if (!TI_BANDGAP_HAS(bgp, COUNTER) &&
+ !TI_BANDGAP_HAS(bgp, COUNTER_DELAY)) {
+ ret = -ENOTSUPP;
+ goto exit;
+ }
+
+ if (TI_BANDGAP_HAS(bgp, COUNTER)) {
+ ti_bandgap_write_counter(bgp, id, interval);
+ goto exit;
+ }
+
+ ret = ti_bandgap_write_counter_delay(bgp, id, interval);
+exit:
+ return ret;
+}
+
+/**
+ * ti_bandgap_read_temperature() - report current temperature
+ * @bgp: pointer to bandgap instance
+ * @id: sensor id
+ * @temperature: resulting temperature
+ *
+ * Return: 0 on success or the proper error code
+ */
+int ti_bandgap_read_temperature(struct ti_bandgap *bgp, int id,
+ int *temperature)
+{
+ u32 temp;
+ int ret;
+
+ ret = ti_bandgap_validate(bgp, id);
+ if (ret)
+ return ret;
+
+ if (!TI_BANDGAP_HAS(bgp, MODE_CONFIG)) {
+ ret = ti_bandgap_force_single_read(bgp, id);
+ if (ret)
+ return ret;
+ }
+
+ spin_lock(&bgp->lock);
+ temp = ti_bandgap_read_temp(bgp, id);
+ spin_unlock(&bgp->lock);
+
+ ret = ti_bandgap_adc_to_mcelsius(bgp, temp, &temp);
+ if (ret)
+ return -EIO;
+
+ *temperature = temp;
+
+ return 0;
+}
+
+/**
+ * ti_bandgap_set_sensor_data() - helper function to store thermal
+ * framework related data.
+ * @bgp: pointer to bandgap instance
+ * @id: sensor id
+ * @data: thermal framework related data to be stored
+ *
+ * Return: 0 on success or the proper error code
+ */
+int ti_bandgap_set_sensor_data(struct ti_bandgap *bgp, int id, void *data)
+{
+ int ret = ti_bandgap_validate(bgp, id);
+ if (ret)
+ return ret;
+
+ bgp->regval[id].data = data;
+
+ return 0;
+}
+
+/**
+ * ti_bandgap_get_sensor_data() - helper function to get thermal
+ * framework related data.
+ * @bgp: pointer to bandgap instance
+ * @id: sensor id
+ *
+ * Return: data stored by set function with sensor id on success or NULL
+ */
+void *ti_bandgap_get_sensor_data(struct ti_bandgap *bgp, int id)
+{
+ int ret = ti_bandgap_validate(bgp, id);
+ if (ret)
+ return ERR_PTR(ret);
+
+ return bgp->regval[id].data;
+}
+
+/*** Helper functions used during device initialization ***/
+
+/**
+ * ti_bandgap_force_single_read() - executes 1 single ADC conversion
+ * @bgp: pointer to struct ti_bandgap
+ * @id: sensor id which it is desired to read 1 temperature
+ *
+ * Used to initialize the conversion state machine and set it to a valid
+ * state. Called during device initialization and context restore events.
+ *
+ * Return: 0
+ */
+static int
+ti_bandgap_force_single_read(struct ti_bandgap *bgp, int id)
+{
+ u32 counter = 1000;
+ struct temp_sensor_registers *tsr;
+
+ /* Select single conversion mode */
+ if (TI_BANDGAP_HAS(bgp, MODE_CONFIG))
+ RMW_BITS(bgp, id, bgap_mode_ctrl, mode_ctrl_mask, 0);
+
+ /* Start of Conversion = 1 */
+ RMW_BITS(bgp, id, temp_sensor_ctrl, bgap_soc_mask, 1);
+
+ /* Wait for EOCZ going up */
+ tsr = bgp->conf->sensors[id].registers;
+
+ while (--counter) {
+ if (ti_bandgap_readl(bgp, tsr->temp_sensor_ctrl) &
+ tsr->bgap_eocz_mask)
+ break;
+ }
+
+ /* Start of Conversion = 0 */
+ RMW_BITS(bgp, id, temp_sensor_ctrl, bgap_soc_mask, 0);
+
+ /* Wait for EOCZ going down */
+ counter = 1000;
+ while (--counter) {
+ if (!(ti_bandgap_readl(bgp, tsr->temp_sensor_ctrl) &
+ tsr->bgap_eocz_mask))
+ break;
+ }
+
+ return 0;
+}
+
+/**
+ * ti_bandgap_set_continuous_mode() - One time enabling of continuous mode
+ * @bgp: pointer to struct ti_bandgap
+ *
+ * Call this function only if HAS(MODE_CONFIG) is set. As this driver may
+ * be used for junction temperature monitoring, it is desirable that the
+ * sensors are operational all the time, so that alerts are generated
+ * properly.
+ *
+ * Return: 0
+ */
+static int ti_bandgap_set_continuous_mode(struct ti_bandgap *bgp)
+{
+ int i;
+
+ for (i = 0; i < bgp->conf->sensor_count; i++) {
+ /* Perform a single read just before enabling continuous */
+ ti_bandgap_force_single_read(bgp, i);
+ RMW_BITS(bgp, i, bgap_mode_ctrl, mode_ctrl_mask, 1);
+ }
+
+ return 0;
+}
+
+/**
+ * ti_bandgap_get_trend() - To fetch the temperature trend of a sensor
+ * @bgp: pointer to struct ti_bandgap
+ * @id: id of the individual sensor
+ * @trend: Pointer to trend.
+ *
+ * This function needs to be called to fetch the temperature trend of a
+ * Particular sensor. The function computes the difference in temperature
+ * w.r.t time. For the bandgaps with built in history buffer the temperatures
+ * are read from the buffer and for those without the Buffer -ENOTSUPP is
+ * returned.
+ *
+ * Return: 0 if no error, else return corresponding error. If no
+ * error then the trend value is passed on to trend parameter
+ */
+int ti_bandgap_get_trend(struct ti_bandgap *bgp, int id, int *trend)
+{
+ struct temp_sensor_registers *tsr;
+ u32 temp1, temp2, reg1, reg2;
+ int t1, t2, interval, ret = 0;
+
+ ret = ti_bandgap_validate(bgp, id);
+ if (ret)
+ goto exit;
+
+ if (!TI_BANDGAP_HAS(bgp, HISTORY_BUFFER) ||
+ !TI_BANDGAP_HAS(bgp, FREEZE_BIT)) {
+ ret = -ENOTSUPP;
+ goto exit;
+ }
+
+ spin_lock(&bgp->lock);
+
+ tsr = bgp->conf->sensors[id].registers;
+
+ /* Freeze and read the last 2 valid readings */
+ RMW_BITS(bgp, id, bgap_mask_ctrl, mask_freeze_mask, 1);
+ reg1 = tsr->ctrl_dtemp_1;
+ reg2 = tsr->ctrl_dtemp_2;
+
+ /* read temperature from history buffer */
+ temp1 = ti_bandgap_readl(bgp, reg1);
+ temp1 &= tsr->bgap_dtemp_mask;
+
+ temp2 = ti_bandgap_readl(bgp, reg2);
+ temp2 &= tsr->bgap_dtemp_mask;
+
+ /* Convert from adc values to mCelsius temperature */
+ ret = ti_bandgap_adc_to_mcelsius(bgp, temp1, &t1);
+ if (ret)
+ goto unfreeze;
+
+ ret = ti_bandgap_adc_to_mcelsius(bgp, temp2, &t2);
+ if (ret)
+ goto unfreeze;
+
+ /* Fetch the update interval */
+ ret = ti_bandgap_read_update_interval(bgp, id, &interval);
+ if (ret)
+ goto unfreeze;
+
+ /* Set the interval to 1 ms if bandgap counter delay is not set */
+ if (interval == 0)
+ interval = 1;
+
+ *trend = (t1 - t2) / interval;
+
+ dev_dbg(bgp->dev, "The temperatures are t1 = %d and t2 = %d and trend =%d\n",
+ t1, t2, *trend);
+
+unfreeze:
+ RMW_BITS(bgp, id, bgap_mask_ctrl, mask_freeze_mask, 0);
+ spin_unlock(&bgp->lock);
+exit:
+ return ret;
+}
+
+/**
+ * ti_bandgap_tshut_init() - setup and initialize tshut handling
+ * @bgp: pointer to struct ti_bandgap
+ * @pdev: pointer to device struct platform_device
+ *
+ * Call this function only in case the bandgap features HAS(TSHUT).
+ * In this case, the driver needs to handle the TSHUT signal as an IRQ.
+ * The IRQ is wired as a GPIO, and for this purpose, it is required
+ * to specify which GPIO line is used. TSHUT IRQ is fired anytime
+ * one of the bandgap sensors violates the TSHUT high/hot threshold.
+ * And in that case, the system must go off.
+ *
+ * Return: 0 if no error, else error status
+ */
+static int ti_bandgap_tshut_init(struct ti_bandgap *bgp,
+ struct platform_device *pdev)
+{
+ int gpio_nr = bgp->tshut_gpio;
+ int status;
+
+ /* Request for gpio_86 line */
+ status = gpio_request(gpio_nr, "tshut");
+ if (status < 0) {
+ dev_err(bgp->dev, "Could not request for TSHUT GPIO:%i\n", 86);
+ return status;
+ }
+ status = gpio_direction_input(gpio_nr);
+ if (status) {
+ dev_err(bgp->dev, "Cannot set input TSHUT GPIO %d\n", gpio_nr);
+ return status;
+ }
+
+ status = request_irq(gpio_to_irq(gpio_nr), ti_bandgap_tshut_irq_handler,
+ IRQF_TRIGGER_RISING, "tshut", NULL);
+ if (status) {
+ gpio_free(gpio_nr);
+ dev_err(bgp->dev, "request irq failed for TSHUT");
+ }
+
+ return 0;
+}
+
+/**
+ * ti_bandgap_alert_init() - setup and initialize talert handling
+ * @bgp: pointer to struct ti_bandgap
+ * @pdev: pointer to device struct platform_device
+ *
+ * Call this function only in case the bandgap features HAS(TALERT).
+ * In this case, the driver needs to handle the TALERT signals as an IRQs.
+ * TALERT is a normal IRQ and it is fired any time thresholds (hot or cold)
+ * are violated. In these situation, the driver must reprogram the thresholds,
+ * accordingly to specified policy.
+ *
+ * Return: 0 if no error, else return corresponding error.
+ */
+static int ti_bandgap_talert_init(struct ti_bandgap *bgp,
+ struct platform_device *pdev)
+{
+ int ret;
+
+ bgp->irq = platform_get_irq(pdev, 0);
+ if (bgp->irq < 0) {
+ dev_err(&pdev->dev, "get_irq failed\n");
+ return bgp->irq;
+ }
+ ret = request_threaded_irq(bgp->irq, NULL,
+ ti_bandgap_talert_irq_handler,
+ IRQF_TRIGGER_HIGH | IRQF_ONESHOT,
+ "talert", bgp);
+ if (ret) {
+ dev_err(&pdev->dev, "Request threaded irq failed.\n");
+ return ret;
+ }
+
+ return 0;
+}
+
+static const struct of_device_id of_ti_bandgap_match[];
+/**
+ * ti_bandgap_build() - parse DT and setup a struct ti_bandgap
+ * @pdev: pointer to device struct platform_device
+ *
+ * Used to read the device tree properties accordingly to the bandgap
+ * matching version. Based on bandgap version and its capabilities it
+ * will build a struct ti_bandgap out of the required DT entries.
+ *
+ * Return: valid bandgap structure if successful, else returns ERR_PTR
+ * return value must be verified with IS_ERR.
+ */
+static struct ti_bandgap *ti_bandgap_build(struct platform_device *pdev)
+{
+ struct device_node *node = pdev->dev.of_node;
+ const struct of_device_id *of_id;
+ struct ti_bandgap *bgp;
+ struct resource *res;
+ int i;
+
+ /* just for the sake */
+ if (!node) {
+ dev_err(&pdev->dev, "no platform information available\n");
+ return ERR_PTR(-EINVAL);
+ }
+
+ bgp = devm_kzalloc(&pdev->dev, sizeof(*bgp), GFP_KERNEL);
+ if (!bgp)
+ return ERR_PTR(-ENOMEM);
+
+ of_id = of_match_device(of_ti_bandgap_match, &pdev->dev);
+ if (of_id)
+ bgp->conf = of_id->data;
+
+ /* register shadow for context save and restore */
+ bgp->regval = devm_kcalloc(&pdev->dev, bgp->conf->sensor_count,
+ sizeof(*bgp->regval), GFP_KERNEL);
+ if (!bgp->regval)
+ return ERR_PTR(-ENOMEM);
+
+ i = 0;
+ do {
+ void __iomem *chunk;
+
+ res = platform_get_resource(pdev, IORESOURCE_MEM, i);
+ if (!res)
+ break;
+ chunk = devm_ioremap_resource(&pdev->dev, res);
+ if (i == 0)
+ bgp->base = chunk;
+ if (IS_ERR(chunk))
+ return ERR_CAST(chunk);
+
+ i++;
+ } while (res);
+
+ if (TI_BANDGAP_HAS(bgp, TSHUT)) {
+ bgp->tshut_gpio = of_get_gpio(node, 0);
+ if (!gpio_is_valid(bgp->tshut_gpio)) {
+ dev_err(&pdev->dev, "invalid gpio for tshut (%d)\n",
+ bgp->tshut_gpio);
+ return ERR_PTR(-EINVAL);
+ }
+ }
+
+ return bgp;
+}
+
+/*** Device driver call backs ***/
+
+static
+int ti_bandgap_probe(struct platform_device *pdev)
+{
+ struct ti_bandgap *bgp;
+ int clk_rate, ret, i;
+
+ bgp = ti_bandgap_build(pdev);
+ if (IS_ERR(bgp)) {
+ dev_err(&pdev->dev, "failed to fetch platform data\n");
+ return PTR_ERR(bgp);
+ }
+ bgp->dev = &pdev->dev;
+
+ if (TI_BANDGAP_HAS(bgp, UNRELIABLE))
+ dev_warn(&pdev->dev,
+ "This OMAP thermal sensor is unreliable. You've been warned\n");
+
+ if (TI_BANDGAP_HAS(bgp, TSHUT)) {
+ ret = ti_bandgap_tshut_init(bgp, pdev);
+ if (ret) {
+ dev_err(&pdev->dev,
+ "failed to initialize system tshut IRQ\n");
+ return ret;
+ }
+ }
+
+ bgp->fclock = clk_get(NULL, bgp->conf->fclock_name);
+ if (IS_ERR(bgp->fclock)) {
+ dev_err(&pdev->dev, "failed to request fclock reference\n");
+ ret = PTR_ERR(bgp->fclock);
+ goto free_irqs;
+ }
+
+ bgp->div_clk = clk_get(NULL, bgp->conf->div_ck_name);
+ if (IS_ERR(bgp->div_clk)) {
+ dev_err(&pdev->dev, "failed to request div_ts_ck clock ref\n");
+ ret = PTR_ERR(bgp->div_clk);
+ goto put_fclock;
+ }
+
+ for (i = 0; i < bgp->conf->sensor_count; i++) {
+ struct temp_sensor_registers *tsr;
+ u32 val;
+
+ tsr = bgp->conf->sensors[i].registers;
+ /*
+ * check if the efuse has a non-zero value if not
+ * it is an untrimmed sample and the temperatures
+ * may not be accurate
+ */
+ val = ti_bandgap_readl(bgp, tsr->bgap_efuse);
+ if (!val)
+ dev_info(&pdev->dev,
+ "Non-trimmed BGAP, Temp not accurate\n");
+ }
+
+ clk_rate = clk_round_rate(bgp->div_clk,
+ bgp->conf->sensors[0].ts_data->max_freq);
+ if (clk_rate < bgp->conf->sensors[0].ts_data->min_freq ||
+ clk_rate <= 0) {
+ ret = -ENODEV;
+ dev_err(&pdev->dev, "wrong clock rate (%d)\n", clk_rate);
+ goto put_clks;
+ }
+
+ ret = clk_set_rate(bgp->div_clk, clk_rate);
+ if (ret)
+ dev_err(&pdev->dev, "Cannot re-set clock rate. Continuing\n");
+
+ bgp->clk_rate = clk_rate;
+ if (TI_BANDGAP_HAS(bgp, CLK_CTRL))
+ clk_prepare_enable(bgp->fclock);
+
+
+ spin_lock_init(&bgp->lock);
+ bgp->dev = &pdev->dev;
+ platform_set_drvdata(pdev, bgp);
+
+ ti_bandgap_power(bgp, true);
+
+ /* Set default counter to 1 for now */
+ if (TI_BANDGAP_HAS(bgp, COUNTER))
+ for (i = 0; i < bgp->conf->sensor_count; i++)
+ RMW_BITS(bgp, i, bgap_counter, counter_mask, 1);
+
+ /* Set default thresholds for alert and shutdown */
+ for (i = 0; i < bgp->conf->sensor_count; i++) {
+ struct temp_sensor_data *ts_data;
+
+ ts_data = bgp->conf->sensors[i].ts_data;
+
+ if (TI_BANDGAP_HAS(bgp, TALERT)) {
+ /* Set initial Talert thresholds */
+ RMW_BITS(bgp, i, bgap_threshold,
+ threshold_tcold_mask, ts_data->t_cold);
+ RMW_BITS(bgp, i, bgap_threshold,
+ threshold_thot_mask, ts_data->t_hot);
+ /* Enable the alert events */
+ RMW_BITS(bgp, i, bgap_mask_ctrl, mask_hot_mask, 1);
+ RMW_BITS(bgp, i, bgap_mask_ctrl, mask_cold_mask, 1);
+ }
+
+ if (TI_BANDGAP_HAS(bgp, TSHUT_CONFIG)) {
+ /* Set initial Tshut thresholds */
+ RMW_BITS(bgp, i, tshut_threshold,
+ tshut_hot_mask, ts_data->tshut_hot);
+ RMW_BITS(bgp, i, tshut_threshold,
+ tshut_cold_mask, ts_data->tshut_cold);
+ }
+ }
+
+ if (TI_BANDGAP_HAS(bgp, MODE_CONFIG))
+ ti_bandgap_set_continuous_mode(bgp);
+
+ /* Set .250 seconds time as default counter */
+ if (TI_BANDGAP_HAS(bgp, COUNTER))
+ for (i = 0; i < bgp->conf->sensor_count; i++)
+ RMW_BITS(bgp, i, bgap_counter, counter_mask,
+ bgp->clk_rate / 4);
+
+ /* Every thing is good? Then expose the sensors */
+ for (i = 0; i < bgp->conf->sensor_count; i++) {
+ char *domain;
+
+ if (bgp->conf->sensors[i].register_cooling) {
+ ret = bgp->conf->sensors[i].register_cooling(bgp, i);
+ if (ret)
+ goto remove_sensors;
+ }
+
+ if (bgp->conf->expose_sensor) {
+ domain = bgp->conf->sensors[i].domain;
+ ret = bgp->conf->expose_sensor(bgp, i, domain);
+ if (ret)
+ goto remove_last_cooling;
+ }
+ }
+
+ /*
+ * Enable the Interrupts once everything is set. Otherwise irq handler
+ * might be called as soon as it is enabled where as rest of framework
+ * is still getting initialised.
+ */
+ if (TI_BANDGAP_HAS(bgp, TALERT)) {
+ ret = ti_bandgap_talert_init(bgp, pdev);
+ if (ret) {
+ dev_err(&pdev->dev, "failed to initialize Talert IRQ\n");
+ i = bgp->conf->sensor_count;
+ goto disable_clk;
+ }
+ }
+
+ return 0;
+
+remove_last_cooling:
+ if (bgp->conf->sensors[i].unregister_cooling)
+ bgp->conf->sensors[i].unregister_cooling(bgp, i);
+remove_sensors:
+ for (i--; i >= 0; i--) {
+ if (bgp->conf->sensors[i].unregister_cooling)
+ bgp->conf->sensors[i].unregister_cooling(bgp, i);
+ if (bgp->conf->remove_sensor)
+ bgp->conf->remove_sensor(bgp, i);
+ }
+ ti_bandgap_power(bgp, false);
+disable_clk:
+ if (TI_BANDGAP_HAS(bgp, CLK_CTRL))
+ clk_disable_unprepare(bgp->fclock);
+put_clks:
+ clk_put(bgp->div_clk);
+put_fclock:
+ clk_put(bgp->fclock);
+free_irqs:
+ if (TI_BANDGAP_HAS(bgp, TSHUT)) {
+ free_irq(gpio_to_irq(bgp->tshut_gpio), NULL);
+ gpio_free(bgp->tshut_gpio);
+ }
+
+ return ret;
+}
+
+static
+int ti_bandgap_remove(struct platform_device *pdev)
+{
+ struct ti_bandgap *bgp = platform_get_drvdata(pdev);
+ int i;
+
+ /* First thing is to remove sensor interfaces */
+ for (i = 0; i < bgp->conf->sensor_count; i++) {
+ if (bgp->conf->sensors[i].unregister_cooling)
+ bgp->conf->sensors[i].unregister_cooling(bgp, i);
+
+ if (bgp->conf->remove_sensor)
+ bgp->conf->remove_sensor(bgp, i);
+ }
+
+ ti_bandgap_power(bgp, false);
+
+ if (TI_BANDGAP_HAS(bgp, CLK_CTRL))
+ clk_disable_unprepare(bgp->fclock);
+ clk_put(bgp->fclock);
+ clk_put(bgp->div_clk);
+
+ if (TI_BANDGAP_HAS(bgp, TALERT))
+ free_irq(bgp->irq, bgp);
+
+ if (TI_BANDGAP_HAS(bgp, TSHUT)) {
+ free_irq(gpio_to_irq(bgp->tshut_gpio), NULL);
+ gpio_free(bgp->tshut_gpio);
+ }
+
+ return 0;
+}
+
+#ifdef CONFIG_PM_SLEEP
+static int ti_bandgap_save_ctxt(struct ti_bandgap *bgp)
+{
+ int i;
+
+ for (i = 0; i < bgp->conf->sensor_count; i++) {
+ struct temp_sensor_registers *tsr;
+ struct temp_sensor_regval *rval;
+
+ rval = &bgp->regval[i];
+ tsr = bgp->conf->sensors[i].registers;
+
+ if (TI_BANDGAP_HAS(bgp, MODE_CONFIG))
+ rval->bg_mode_ctrl = ti_bandgap_readl(bgp,
+ tsr->bgap_mode_ctrl);
+ if (TI_BANDGAP_HAS(bgp, COUNTER))
+ rval->bg_counter = ti_bandgap_readl(bgp,
+ tsr->bgap_counter);
+ if (TI_BANDGAP_HAS(bgp, TALERT)) {
+ rval->bg_threshold = ti_bandgap_readl(bgp,
+ tsr->bgap_threshold);
+ rval->bg_ctrl = ti_bandgap_readl(bgp,
+ tsr->bgap_mask_ctrl);
+ }
+
+ if (TI_BANDGAP_HAS(bgp, TSHUT_CONFIG))
+ rval->tshut_threshold = ti_bandgap_readl(bgp,
+ tsr->tshut_threshold);
+ }
+
+ return 0;
+}
+
+static int ti_bandgap_restore_ctxt(struct ti_bandgap *bgp)
+{
+ int i;
+
+ for (i = 0; i < bgp->conf->sensor_count; i++) {
+ struct temp_sensor_registers *tsr;
+ struct temp_sensor_regval *rval;
+ u32 val = 0;
+
+ rval = &bgp->regval[i];
+ tsr = bgp->conf->sensors[i].registers;
+
+ if (TI_BANDGAP_HAS(bgp, COUNTER))
+ val = ti_bandgap_readl(bgp, tsr->bgap_counter);
+
+ if (TI_BANDGAP_HAS(bgp, TSHUT_CONFIG))
+ ti_bandgap_writel(bgp, rval->tshut_threshold,
+ tsr->tshut_threshold);
+ /* Force immediate temperature measurement and update
+ * of the DTEMP field
+ */
+ ti_bandgap_force_single_read(bgp, i);
+
+ if (TI_BANDGAP_HAS(bgp, COUNTER))
+ ti_bandgap_writel(bgp, rval->bg_counter,
+ tsr->bgap_counter);
+ if (TI_BANDGAP_HAS(bgp, MODE_CONFIG))
+ ti_bandgap_writel(bgp, rval->bg_mode_ctrl,
+ tsr->bgap_mode_ctrl);
+ if (TI_BANDGAP_HAS(bgp, TALERT)) {
+ ti_bandgap_writel(bgp, rval->bg_threshold,
+ tsr->bgap_threshold);
+ ti_bandgap_writel(bgp, rval->bg_ctrl,
+ tsr->bgap_mask_ctrl);
+ }
+ }
+
+ return 0;
+}
+
+static int ti_bandgap_suspend(struct device *dev)
+{
+ struct ti_bandgap *bgp = dev_get_drvdata(dev);
+ int err;
+
+ err = ti_bandgap_save_ctxt(bgp);
+ ti_bandgap_power(bgp, false);
+
+ if (TI_BANDGAP_HAS(bgp, CLK_CTRL))
+ clk_disable_unprepare(bgp->fclock);
+
+ return err;
+}
+
+static int ti_bandgap_resume(struct device *dev)
+{
+ struct ti_bandgap *bgp = dev_get_drvdata(dev);
+
+ if (TI_BANDGAP_HAS(bgp, CLK_CTRL))
+ clk_prepare_enable(bgp->fclock);
+
+ ti_bandgap_power(bgp, true);
+
+ return ti_bandgap_restore_ctxt(bgp);
+}
+static SIMPLE_DEV_PM_OPS(ti_bandgap_dev_pm_ops, ti_bandgap_suspend,
+ ti_bandgap_resume);
+
+#define DEV_PM_OPS (&ti_bandgap_dev_pm_ops)
+#else
+#define DEV_PM_OPS NULL
+#endif
+
+static const struct of_device_id of_ti_bandgap_match[] = {
+#ifdef CONFIG_OMAP3_THERMAL
+ {
+ .compatible = "ti,omap34xx-bandgap",
+ .data = (void *)&omap34xx_data,
+ },
+ {
+ .compatible = "ti,omap36xx-bandgap",
+ .data = (void *)&omap36xx_data,
+ },
+#endif
+#ifdef CONFIG_OMAP4_THERMAL
+ {
+ .compatible = "ti,omap4430-bandgap",
+ .data = (void *)&omap4430_data,
+ },
+ {
+ .compatible = "ti,omap4460-bandgap",
+ .data = (void *)&omap4460_data,
+ },
+ {
+ .compatible = "ti,omap4470-bandgap",
+ .data = (void *)&omap4470_data,
+ },
+#endif
+#ifdef CONFIG_OMAP5_THERMAL
+ {
+ .compatible = "ti,omap5430-bandgap",
+ .data = (void *)&omap5430_data,
+ },
+#endif
+#ifdef CONFIG_DRA752_THERMAL
+ {
+ .compatible = "ti,dra752-bandgap",
+ .data = (void *)&dra752_data,
+ },
+#endif
+ /* Sentinel */
+ { },
+};
+MODULE_DEVICE_TABLE(of, of_ti_bandgap_match);
+
+static struct platform_driver ti_bandgap_sensor_driver = {
+ .probe = ti_bandgap_probe,
+ .remove = ti_bandgap_remove,
+ .driver = {
+ .name = "ti-soc-thermal",
+ .pm = DEV_PM_OPS,
+ .of_match_table = of_ti_bandgap_match,
+ },
+};
+
+module_platform_driver(ti_bandgap_sensor_driver);
+
+MODULE_DESCRIPTION("OMAP4+ bandgap temperature sensor driver");
+MODULE_LICENSE("GPL v2");
+MODULE_ALIAS("platform:ti-soc-thermal");
+MODULE_AUTHOR("Texas Instrument Inc.");