diff options
Diffstat (limited to 'drivers/thermal/ti-soc-thermal/ti-bandgap.c')
| -rw-r--r-- | drivers/thermal/ti-soc-thermal/ti-bandgap.c | 1546 |
1 files changed, 1546 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 000000000000..f20c1cfe9800 --- /dev/null +++ b/drivers/thermal/ti-soc-thermal/ti-bandgap.c @@ -0,0 +1,1546 @@ +/* + * 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/io.h> + +#include "ti-bandgap.h" + +/*** 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, ret = 0; + + if (!TI_BANDGAP_HAS(bgp, POWER_SWITCH)) { + ret = -ENOTSUPP; + goto exit; + } + + for (i = 0; i < bgp->conf->sensor_count; i++) + /* active on 0 */ + RMW_BITS(bgp, i, temp_sensor_ctrl, bgap_tempsoff_mask, !on); + +exit: + return ret; +} + +/** + * 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 */ + 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; + int ret = 0; + + /* look up for temperature in the table and return the temperature */ + if (adc_val < conf->adc_start_val || adc_val > conf->adc_end_val) { + ret = -ERANGE; + goto exit; + } + + *t = bgp->conf->conv_table[adc_val - conf->adc_start_val]; + +exit: + return ret; +} + +/** + * ti_bandgap_mcelsius_to_adc() - converts a mCelsius value to ADC scale + * @bgp: struct ti_bandgap pointer + * @temp: value in mCelsius + * @adc: address where to write the resulting temperature in ADC representation + * + * Simple conversion from mCelsius to ADC values. In case the temp 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 @temp + * argument is out of the ADC conv table range. + */ +static +int ti_bandgap_mcelsius_to_adc(struct ti_bandgap *bgp, long temp, int *adc) +{ + const struct ti_bandgap_data *conf = bgp->conf; + const int *conv_table = bgp->conf->conv_table; + int high, low, mid, ret = 0; + + low = 0; + high = conf->adc_end_val - conf->adc_start_val; + mid = (high + low) / 2; + + if (temp < conv_table[low] || temp > conv_table[high]) { + ret = -ERANGE; + goto exit; + } + + while (low < high) { + if (temp < conv_table[mid]) + high = mid - 1; + else + low = mid + 1; + mid = (low + high) / 2; + } + + *adc = conf->adc_start_val + low; + +exit: + return ret; +} + +/** + * ti_bandgap_add_hyst() - add hysteresis (in mCelsius) to an ADC value + * @bgp: struct ti_bandgap pointer + * @adc_val: temperature value in ADC representation + * @hyst_val: hysteresis value in mCelsius + * @sum: address where to write the resulting temperature (in ADC scale) + * + * Adds an hysteresis value (in mCelsius) to a ADC temperature value. + * + * Return: 0 on success, -ERANGE otherwise. + */ +static +int ti_bandgap_add_hyst(struct ti_bandgap *bgp, int adc_val, int hyst_val, + u32 *sum) +{ + int temp, ret; + + /* + * Need to add in the mcelsius domain, so we have a temperature + * the conv_table range + */ + ret = ti_bandgap_adc_to_mcelsius(bgp, adc_val, &temp); + if (ret < 0) + goto exit; + + temp += hyst_val; + + ret = ti_bandgap_mcelsius_to_adc(bgp, temp, sum); + +exit: + return ret; +} + +/*** Helper functions handling device Alert/Shutdown signals ***/ + +/** + * ti_bandgap_unmask_interrupts() - unmasks the events of thot & tcold + * @bgp: struct ti_bandgap pointer + * @id: bandgap sensor id + * @t_hot: hot temperature value to trigger alert signal + * @t_cold: cold temperature value to trigger alert signal + * + * Checks the requested t_hot and t_cold values and configures the IRQ event + * masks accordingly. Call this function only if bandgap features HAS(TALERT). + */ +static void ti_bandgap_unmask_interrupts(struct ti_bandgap *bgp, int id, + u32 t_hot, u32 t_cold) +{ + struct temp_sensor_registers *tsr; + u32 temp, reg_val; + + /* Read the current on die temperature */ + temp = ti_bandgap_read_temp(bgp, id); + + tsr = bgp->conf->sensors[id].registers; + reg_val = ti_bandgap_readl(bgp, tsr->bgap_mask_ctrl); + + if (temp < t_hot) + reg_val |= tsr->mask_hot_mask; + else + reg_val &= ~tsr->mask_hot_mask; + + if (t_cold < temp) + reg_val |= tsr->mask_cold_mask; + else + reg_val &= ~tsr->mask_cold_mask; + ti_bandgap_writel(bgp, reg_val, tsr->bgap_mask_ctrl); +} + +/** + * ti_bandgap_update_alert_threshold() - sequence to update thresholds + * @bgp: struct ti_bandgap pointer + * @id: bandgap sensor id + * @val: value (ADC) of a new threshold + * @hot: desired threshold to be updated. true if threshold hot, false if + * threshold cold + * + * It will program the required thresholds (hot and cold) for TALERT signal. + * This function can be used to update t_hot or t_cold, depending on @hot value. + * It checks the resulting t_hot and t_cold values, based on the new passed @val + * and configures the thresholds so that t_hot is always greater than t_cold. + * Call this function only if bandgap features HAS(TALERT). + * + * Return: 0 if no error, else corresponding error + */ +static int ti_bandgap_update_alert_threshold(struct ti_bandgap *bgp, int id, + int val, bool hot) +{ + struct temp_sensor_data *ts_data = bgp->conf->sensors[id].ts_data; + struct temp_sensor_registers *tsr; + u32 thresh_val, reg_val, t_hot, t_cold; + int err = 0; + + tsr = bgp->conf->sensors[id].registers; + + /* obtain the current value */ + thresh_val = ti_bandgap_readl(bgp, tsr->bgap_threshold); + t_cold = (thresh_val & tsr->threshold_tcold_mask) >> + __ffs(tsr->threshold_tcold_mask); + t_hot = (thresh_val & tsr->threshold_thot_mask) >> + __ffs(tsr->threshold_thot_mask); + if (hot) + t_hot = val; + else + t_cold = val; + + if (t_cold > t_hot) { + if (hot) + err = ti_bandgap_add_hyst(bgp, t_hot, + -ts_data->hyst_val, + &t_cold); + else + err = ti_bandgap_add_hyst(bgp, t_cold, + ts_data->hyst_val, + &t_hot); + } + + /* write the new threshold values */ + reg_val = thresh_val & + ~(tsr->threshold_thot_mask | tsr->threshold_tcold_mask); + reg_val |= (t_hot << __ffs(tsr->threshold_thot_mask)) | + (t_cold << __ffs(tsr->threshold_tcold_mask)); + ti_bandgap_writel(bgp, reg_val, tsr->bgap_threshold); + + if (err) { + dev_err(bgp->dev, "failed to reprogram thot threshold\n"); + err = -EIO; + goto exit; + } + + ti_bandgap_unmask_interrupts(bgp, id, t_hot, t_cold); +exit: + return err; +} + +/** + * 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) +{ + int ret = 0; + + if (IS_ERR_OR_NULL(bgp)) { + pr_err("%s: invalid bandgap pointer\n", __func__); + ret = -EINVAL; + goto exit; + } + + if ((id < 0) || (id >= bgp->conf->sensor_count)) { + dev_err(bgp->dev, "%s: sensor id out of range (%d)\n", + __func__, id); + ret = -ERANGE; + } + +exit: + return ret; +} + +/** + * _ti_bandgap_write_threshold() - helper to update TALERT t_cold or t_hot + * @bgp: struct ti_bandgap pointer + * @id: bandgap sensor id + * @val: value (mCelsius) of a new threshold + * @hot: desired threshold to be updated. true if threshold hot, false if + * threshold cold + * + * It will update the required thresholds (hot and cold) for TALERT signal. + * This function can be used to update t_hot or t_cold, depending on @hot value. + * Validates the mCelsius range and update the requested threshold. + * Call this function only if bandgap features HAS(TALERT). + * + * Return: 0 if no error, else corresponding error value. + */ +static int _ti_bandgap_write_threshold(struct ti_bandgap *bgp, int id, int val, + bool hot) +{ + struct temp_sensor_data *ts_data; + struct temp_sensor_registers *tsr; + u32 adc_val; + int ret; + + ret = ti_bandgap_validate(bgp, id); + if (ret) + goto exit; + + if (!TI_BANDGAP_HAS(bgp, TALERT)) { + ret = -ENOTSUPP; + goto exit; + } + + ts_data = bgp->conf->sensors[id].ts_data; + tsr = bgp->conf->sensors[id].registers; + if (hot) { + if (val < ts_data->min_temp + ts_data->hyst_val) + ret = -EINVAL; + } else { + if (val > ts_data->max_temp + ts_data->hyst_val) + ret = -EINVAL; + } + + if (ret) + goto exit; + + ret = ti_bandgap_mcelsius_to_adc(bgp, val, &adc_val); + if (ret < 0) + goto exit; + + spin_lock(&bgp->lock); + ret = ti_bandgap_update_alert_threshold(bgp, id, adc_val, hot); + spin_unlock(&bgp->lock); + +exit: + return ret; +} + +/** + * _ti_bandgap_read_threshold() - helper to read TALERT t_cold or t_hot + * @bgp: struct ti_bandgap pointer + * @id: bandgap sensor id + * @val: value (mCelsius) of a threshold + * @hot: desired threshold to be read. true if threshold hot, false if + * threshold cold + * + * It will fetch the required thresholds (hot and cold) for TALERT signal. + * This function can be used to read t_hot or t_cold, depending on @hot value. + * Call this function only if bandgap features HAS(TALERT). + * + * Return: 0 if no error, -ENOTSUPP if it has no TALERT support, or the + * corresponding error value if some operation fails. + */ +static int _ti_bandgap_read_threshold(struct ti_bandgap *bgp, int id, + int *val, bool hot) +{ + struct temp_sensor_registers *tsr; + u32 temp, mask; + int ret = 0; + + ret = ti_bandgap_validate(bgp, id); + if (ret) + goto exit; + + if (!TI_BANDGAP_HAS(bgp, TALERT)) { + ret = -ENOTSUPP; + goto exit; + } + + tsr = bgp->conf->sensors[id].registers; + if (hot) + mask = tsr->threshold_thot_mask; + else + mask = tsr->threshold_tcold_mask; + + temp = ti_bandgap_readl(bgp, tsr->bgap_threshold); + temp = (temp & mask) >> __ffs(mask); + ret |= ti_bandgap_adc_to_mcelsius(bgp, temp, &temp); + if (ret) { + dev_err(bgp->dev, "failed to read thot\n"); + ret = -EIO; + goto exit; + } + + *val = temp; + +exit: + return ret; +} + +/*** Exposed APIs ***/ + +/** + * ti_bandgap_read_thot() - reads sensor current thot + * @bgp: pointer to bandgap instance + * @id: sensor id + * @thot: resulting current thot value + * + * Return: 0 on success or the proper error code + */ +int ti_bandgap_read_thot(struct ti_bandgap *bgp, int id, int *thot) +{ + return _ti_bandgap_read_threshold(bgp, id, thot, true); +} + +/** + * ti_bandgap_write_thot() - sets sensor current thot + * @bgp: pointer to bandgap instance + * @id: sensor id + * @val: desired thot value + * + * Return: 0 on success or the proper error code + */ +int ti_bandgap_write_thot(struct ti_bandgap *bgp, int id, int val) +{ + return _ti_bandgap_write_threshold(bgp, id, val, true); +} + +/** + * ti_bandgap_read_tcold() - reads sensor current tcold + * @bgp: pointer to bandgap instance + * @id: sensor id + * @tcold: resulting current tcold value + * + * Return: 0 on success or the proper error code + */ +int ti_bandgap_read_tcold(struct ti_bandgap *bgp, int id, int *tcold) +{ + return _ti_bandgap_read_threshold(bgp, id, tcold, false); +} + +/** + * ti_bandgap_write_tcold() - sets the sensor tcold + * @bgp: pointer to bandgap instance + * @id: sensor id + * @val: desired tcold value + * + * Return: 0 on success or the proper error code + */ +int ti_bandgap_write_tcold(struct ti_bandgap *bgp, int id, int val) +{ + return _ti_bandgap_write_threshold(bgp, id, val, false); +} + +/** + * 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; + + 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 temp = 0, counter = 1000; + + /* 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 until DTEMP is updated */ + temp = ti_bandgap_read_temp(bgp, id); + + while ((temp == 0) && --counter) + temp = ti_bandgap_read_temp(bgp, id); + /* REVISIT: Check correct condition for end of conversion */ + + /* Start of Conversion = 0 */ + RMW_BITS(bgp, id, temp_sensor_ctrl, bgap_soc_mask, 0); + + return 0; +} + +/** + * ti_bandgap_set_continous_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; + } + + tsr = bgp->conf->sensors[id].registers; + + /* Freeze and read the last 2 valid readings */ + 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 exit; + + ret = ti_bandgap_adc_to_mcelsius(bgp, temp2, &t2); + if (ret) + goto exit; + + /* Fetch the update interval */ + ret = ti_bandgap_read_update_interval(bgp, id, &interval); + if (ret || !interval) + goto exit; + + *trend = (t1 - t2) / interval; + + dev_dbg(bgp->dev, "The temperatures are t1 = %d and t2 = %d and trend =%d\n", + t1, t2, *trend); + +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; + u32 prop; + 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) { + dev_err(&pdev->dev, "Unable to allocate mem for driver ref\n"); + 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_kzalloc(&pdev->dev, sizeof(*bgp->regval) * + bgp->conf->sensor_count, GFP_KERNEL); + if (!bgp) { + dev_err(&pdev->dev, "Unable to allocate mem for driver ref\n"); + 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)) { + if (of_property_read_u32(node, "ti,tshut-gpio", &prop) < 0) { + dev_err(&pdev->dev, "missing tshut gpio in device tree\n"); + return ERR_PTR(-EINVAL); + } + bgp->tshut_gpio = prop; + 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 = 0, i; + + bgp = ti_bandgap_build(pdev); + if (IS_ERR_OR_NULL(bgp)) { + dev_err(&pdev->dev, "failed to fetch platform data\n"); + return PTR_ERR(bgp); + } + bgp->dev = &pdev->dev; + + 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); + ret = IS_ERR_OR_NULL(bgp->fclock); + if (ret) { + dev_err(&pdev->dev, "failed to request fclock reference\n"); + goto free_irqs; + } + + bgp->div_clk = clk_get(NULL, bgp->conf->div_ck_name); + ret = IS_ERR_OR_NULL(bgp->div_clk); + if (ret) { + dev_err(&pdev->dev, + "failed to request div_ts_ck clock ref\n"); + goto free_irqs; + } + + 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 (ret || !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 == 0xffffffff) { + 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->fclock); + clk_put(bgp->div_clk); +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 +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 const struct dev_pm_ops ti_bandgap_dev_pm_ops = { + SET_SYSTEM_SLEEP_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_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 + /* 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."); |