/* * 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_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; low = 0; high = conf->adc_end_val - conf->adc_start_val; mid = (high + low) / 2; if (temp < conv_table[low] || temp > conv_table[high]) return -ERANGE; 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; return 0; } /** * 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) return ret; temp += hyst_val; ret = ti_bandgap_mcelsius_to_adc(bgp, temp, sum); 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, ctrl; 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)); /** * Errata i813: * Spurious Thermal Alert: Talert can happen randomly while the device * remains under the temperature limit defined for this event to trig. * This spurious event is caused by a incorrect re-synchronization * between clock domains. The comparison between configured threshold * and current temperature value can happen while the value is * transitioning (metastable), thus causing inappropriate event * generation. No spurious event occurs as long as the threshold value * stays unchanged. Spurious event can be generated while a thermal * alert threshold is modified in * CONTROL_BANDGAP_THRESHOLD_MPU/GPU/CORE/DSPEVE/IVA_n. */ if (TI_BANDGAP_HAS(bgp, ERRATA_813)) { /* Mask t_hot and t_cold events at the IP Level */ ctrl = ti_bandgap_readl(bgp, tsr->bgap_mask_ctrl); if (hot) ctrl &= ~tsr->mask_hot_mask; else ctrl &= ~tsr->mask_cold_mask; ti_bandgap_writel(bgp, ctrl, tsr->bgap_mask_ctrl); } /* Write the threshold value */ ti_bandgap_writel(bgp, reg_val, tsr->bgap_threshold); if (TI_BANDGAP_HAS(bgp, ERRATA_813)) { /* Unmask t_hot and t_cold events at the IP Level */ ctrl = ti_bandgap_readl(bgp, tsr->bgap_mask_ctrl); if (hot) ctrl |= tsr->mask_hot_mask; else ctrl |= tsr->mask_cold_mask; ti_bandgap_writel(bgp, ctrl, tsr->bgap_mask_ctrl); } 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) { 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_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) return ret; if (!TI_BANDGAP_HAS(bgp, TALERT)) return -ENOTSUPP; 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) return ret; ret = ti_bandgap_mcelsius_to_adc(bgp, val, &adc_val); if (ret < 0) return ret; spin_lock(&bgp->lock); ret = ti_bandgap_update_alert_threshold(bgp, id, adc_val, hot); spin_unlock(&bgp->lock); 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; 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_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; } 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) { 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->regval) { 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)) { 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.");