Return-Path: Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1752111AbdFAPo4 (ORCPT ); Thu, 1 Jun 2017 11:44:56 -0400 Received: from shadbolt.e.decadent.org.uk ([88.96.1.126]:33253 "EHLO shadbolt.e.decadent.org.uk" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1752072AbdFAPox (ORCPT ); Thu, 1 Jun 2017 11:44:53 -0400 Content-Type: text/plain; charset="UTF-8" Content-Disposition: inline Content-Transfer-Encoding: 8bit MIME-Version: 1.0 From: Ben Hutchings To: linux-kernel@vger.kernel.org, stable@vger.kernel.org CC: akpm@linux-foundation.org, "Mark Greer" , "Tony Lindgren" , "Liam Breck" , "Sebastian Reichel" , "Liam Breck" Date: Thu, 01 Jun 2017 16:43:15 +0100 Message-ID: X-Mailer: LinuxStableQueue (scripts by bwh) Subject: [PATCH 3.16 063/212] power: supply: bq24190_charger: Don't read fault register outside irq_handle_thread() In-Reply-To: X-SA-Exim-Connect-IP: 82.70.136.246 X-SA-Exim-Mail-From: ben@decadent.org.uk X-SA-Exim-Scanned: No (on shadbolt.decadent.org.uk); SAEximRunCond expanded to false Sender: linux-kernel-owner@vger.kernel.org List-ID: X-Mailing-List: linux-kernel@vger.kernel.org Content-Length: 6544 Lines: 211 3.16.44-rc1 review patch. If anyone has any objections, please let me know. ------------------ From: Liam Breck commit 68abfb8015832ddf728b911769659468efaf8bd9 upstream. Caching the fault register after a single I2C read may not keep an accurate value. Fix by doing two reads in irq_handle_thread() and using the cached value elsewhere. If a safety timer fault later clears itself, we apparently don't get an interrupt (INT), however other interrupts would refresh the register cache. =46romthe data sheet: "When a fault occurs, the charger device sends out INT and keeps the fault state in REG09 until the host reads the fault register. Before the host reads REG09 and all the faults are cleared, the charger device would not send any INT upon new faults. In order to read the current fault status, the host has to read REG09 two times consecutively. The 1st reads fault register status from the last read [1] and the 2nd reads the current fault register status." [1] presumably a typo; should be "last fault" Fixes: d7bf353fd0aa3 ("bq24190_charger: Add support for TI BQ24190 Battery Charger") Signed-off-by: Liam Breck Acked-by: Mark Greer Acked-by: Tony Lindgren Signed-off-by: Sebastian Reichel [bwh: Backported to 3.16: adjust filename] Signed-off-by: Ben Hutchings --- drivers/power/bq24190_charger.c | 94 ++++++++++------------------------ 1 file changed, 27 insertions(+), 67 deletions(-) --- a/drivers/power/bq24190_charger.c +++ b/drivers/power/bq24190_charger.c @@ -144,10 +144,7 @@ * so the first read after a fault returns the latched value and subsequent * reads return the current value. In order to return the fault status * to the user, have the interrupt handler save the reg's value and retrieve - * it in the appropriate health/status routine. Each routine has its own - * flag indicating whether it should use the value stored by the last run - * of the interrupt handler or do an actual reg read. That way each routine - * can report back whatever fault may have occured. + * it in the appropriate health/status routine. */ struct bq24190_dev_info { struct i2c_client *client; @@ -159,9 +156,6 @@ struct bq24190_dev_info { unsigned int gpio_int; unsigned int irq; struct mutex f_reg_lock; - bool charger_health_valid; - bool battery_health_valid; - bool battery_status_valid; u8 f_reg; u8 ss_reg; u8 watchdog; @@ -637,21 +631,11 @@ static int bq24190_charger_get_health(st union power_supply_propval *val) { u8 v; - int health, ret; + int health; mutex_lock(&bdi->f_reg_lock); - - if (bdi->charger_health_valid) { - v = bdi->f_reg; - bdi->charger_health_valid = false; - mutex_unlock(&bdi->f_reg_lock); - } else { - mutex_unlock(&bdi->f_reg_lock); - - ret = bq24190_read(bdi, BQ24190_REG_F, &v); - if (ret < 0) - return ret; - } + v = bdi->f_reg; + mutex_unlock(&bdi->f_reg_lock); if (v & BQ24190_REG_F_BOOST_FAULT_MASK) { /* @@ -943,18 +927,8 @@ static int bq24190_battery_get_status(st int status, ret; mutex_lock(&bdi->f_reg_lock); - - if (bdi->battery_status_valid) { - chrg_fault = bdi->f_reg; - bdi->battery_status_valid = false; - mutex_unlock(&bdi->f_reg_lock); - } else { - mutex_unlock(&bdi->f_reg_lock); - - ret = bq24190_read(bdi, BQ24190_REG_F, &chrg_fault); - if (ret < 0) - return ret; - } + chrg_fault = bdi->f_reg; + mutex_unlock(&bdi->f_reg_lock); chrg_fault &= BQ24190_REG_F_CHRG_FAULT_MASK; chrg_fault >>= BQ24190_REG_F_CHRG_FAULT_SHIFT; @@ -1002,21 +976,11 @@ static int bq24190_battery_get_health(st union power_supply_propval *val) { u8 v; - int health, ret; + int health; mutex_lock(&bdi->f_reg_lock); - - if (bdi->battery_health_valid) { - v = bdi->f_reg; - bdi->battery_health_valid = false; - mutex_unlock(&bdi->f_reg_lock); - } else { - mutex_unlock(&bdi->f_reg_lock); - - ret = bq24190_read(bdi, BQ24190_REG_F, &v); - if (ret < 0) - return ret; - } + v = bdi->f_reg; + mutex_unlock(&bdi->f_reg_lock); if (v & BQ24190_REG_F_BAT_FAULT_MASK) { health = POWER_SUPPLY_HEALTH_OVERVOLTAGE; @@ -1211,7 +1175,7 @@ static irqreturn_t bq24190_irq_handler_t | BQ24190_REG_F_NTC_FAULT_MASK; bool alert_charger = false, alert_battery = false; u8 ss_reg = 0, f_reg = 0; - int ret; + int i, ret; pm_runtime_get_sync(bdi->dev); @@ -1241,33 +1205,35 @@ static irqreturn_t bq24190_irq_handler_t alert_battery = true; if ((bdi->ss_reg & ~battery_mask_ss) != (ss_reg & ~battery_mask_ss)) alert_charger = true; - bdi->ss_reg = ss_reg; } - mutex_lock(&bdi->f_reg_lock); - - ret = bq24190_read(bdi, BQ24190_REG_F, &f_reg); - if (ret < 0) { - mutex_unlock(&bdi->f_reg_lock); - dev_err(bdi->dev, "Can't read F reg: %d\n", ret); - goto out; - } + i = 0; + do { + ret = bq24190_read(bdi, BQ24190_REG_F, &f_reg); + if (ret < 0) { + dev_err(bdi->dev, "Can't read F reg: %d\n", ret); + goto out; + } + } while (f_reg && ++i < 2); if (f_reg != bdi->f_reg) { + dev_info(bdi->dev, + "Fault: boost %d, charge %d, battery %d, ntc %d\n", + !!(f_reg & BQ24190_REG_F_BOOST_FAULT_MASK), + !!(f_reg & BQ24190_REG_F_CHRG_FAULT_MASK), + !!(f_reg & BQ24190_REG_F_BAT_FAULT_MASK), + !!(f_reg & BQ24190_REG_F_NTC_FAULT_MASK)); + + mutex_lock(&bdi->f_reg_lock); if ((bdi->f_reg & battery_mask_f) != (f_reg & battery_mask_f)) alert_battery = true; if ((bdi->f_reg & ~battery_mask_f) != (f_reg & ~battery_mask_f)) alert_charger = true; - bdi->f_reg = f_reg; - bdi->charger_health_valid = true; - bdi->battery_health_valid = true; - bdi->battery_status_valid = true; + mutex_unlock(&bdi->f_reg_lock); } - mutex_unlock(&bdi->f_reg_lock); - if (alert_charger) power_supply_changed(&bdi->charger); if (alert_battery) @@ -1386,9 +1352,6 @@ static int bq24190_probe(struct i2c_clie mutex_init(&bdi->f_reg_lock); bdi->f_reg = 0; bdi->ss_reg = BQ24190_REG_SS_VBUS_STAT_MASK; /* impossible state */ - bdi->charger_health_valid = false; - bdi->battery_health_valid = false; - bdi->battery_status_valid = false; i2c_set_clientdata(client, bdi); @@ -1497,9 +1460,6 @@ static int bq24190_pm_resume(struct devi bdi->f_reg = 0; bdi->ss_reg = BQ24190_REG_SS_VBUS_STAT_MASK; /* impossible state */ - bdi->charger_health_valid = false; - bdi->battery_health_valid = false; - bdi->battery_status_valid = false; pm_runtime_get_sync(bdi->dev); bq24190_register_reset(bdi);