From c9b0fa310ccc735f11afe52d3b14021c607931e4 Mon Sep 17 00:00:00 2001 From: Przemyslaw Marczak Date: Mon, 30 Dec 2013 11:24:32 +0100 Subject: [PATCH] fuelgauge: max17042: fix i2c read issue which causes infinity loop. Issues: - reading i2c data by passing u16 pointer causes errors in read data. - max17042 status register fields have not only Power On Reset meaning so using proper mask is required. Changes: - read i2c data to type u32 instead of u16 - avoids buffer overflow - compare FG status register using mask not just one bit value - add checking return value to functions fg read/write - add model lock and model check count - add debug msg Signed-off-by: Przemyslaw Marczak Cc: Lukasz Majewski Cc: Minkyu Kang --- drivers/power/fuel_gauge/fg_max17042.c | 120 ++++++++++++++++++------- 1 file changed, 86 insertions(+), 34 deletions(-) diff --git a/drivers/power/fuel_gauge/fg_max17042.c b/drivers/power/fuel_gauge/fg_max17042.c index c285747f34..154ca6a695 100644 --- a/drivers/power/fuel_gauge/fg_max17042.c +++ b/drivers/power/fuel_gauge/fg_max17042.c @@ -20,21 +20,30 @@ static int fg_write_regs(struct pmic *p, u8 addr, u16 *data, int num) int ret = 0; int i; - for (i = 0; i < num; i++, addr++) - ret |= pmic_reg_write(p, addr, *(data + i)); + for (i = 0; i < num; i++, addr++) { + ret = pmic_reg_write(p, addr, *(data + i)); + if (ret) + return ret; + } - return ret; + return 0; } static int fg_read_regs(struct pmic *p, u8 addr, u16 *data, int num) { + unsigned int dat; int ret = 0; int i; - for (i = 0; i < num; i++, addr++) - ret |= pmic_reg_read(p, addr, (u32 *) (data + i)); + for (i = 0; i < num; i++, addr++) { + ret = pmic_reg_read(p, addr, &dat); + if (ret) + return ret; - return ret; + *(data + i) = (u16)dat; + } + + return 0; } static int fg_write_and_verify(struct pmic *p, u8 addr, u16 data) @@ -57,9 +66,13 @@ static int fg_write_and_verify(struct pmic *p, u8 addr, u16 data) static void por_fuelgauge_init(struct pmic *p) { u16 r_data0[16], r_data1[16], r_data2[16]; - u32 rewrite_count = 5, i = 0; - unsigned int val; - int ret = 0; + u32 rewrite_count = 5; + u32 check_count; + u32 lock_count; + u32 i = 0; + u32 val; + s32 ret = 0; + char *status_msg; /* Delay 500 ms */ mdelay(500); @@ -67,29 +80,55 @@ static void por_fuelgauge_init(struct pmic *p) pmic_reg_write(p, MAX17042_CONFIG, 0x2310); rewrite_model: + check_count = 5; + lock_count = 5; + + if (!rewrite_count--) { + status_msg = "init failed!"; + goto error; + } + /* Unlock Model Access */ pmic_reg_write(p, MAX17042_MLOCKReg1, MODEL_UNLOCK1); pmic_reg_write(p, MAX17042_MLOCKReg2, MODEL_UNLOCK2); /* Write/Read/Verify the Custom Model */ - ret |= fg_write_regs(p, MAX17042_MODEL1, cell_character0, + ret = fg_write_regs(p, MAX17042_MODEL1, cell_character0, ARRAY_SIZE(cell_character0)); - ret |= fg_write_regs(p, MAX17042_MODEL2, cell_character1, + if (ret) + goto rewrite_model; + + ret = fg_write_regs(p, MAX17042_MODEL2, cell_character1, ARRAY_SIZE(cell_character1)); - ret |= fg_write_regs(p, MAX17042_MODEL3, cell_character2, + if (ret) + goto rewrite_model; + + ret = fg_write_regs(p, MAX17042_MODEL3, cell_character2, ARRAY_SIZE(cell_character2)); + if (ret) + goto rewrite_model; - if (ret) { - printf("%s: Cell parameters write failed!\n", __func__); - return; +check_model: + if (!check_count--) { + if (rewrite_count) + goto rewrite_model; + else + status_msg = "check failed!"; + + goto error; } - ret |= fg_read_regs(p, MAX17042_MODEL1, r_data0, ARRAY_SIZE(r_data0)); - ret |= fg_read_regs(p, MAX17042_MODEL2, r_data1, ARRAY_SIZE(r_data1)); - ret |= fg_read_regs(p, MAX17042_MODEL3, r_data2, ARRAY_SIZE(r_data2)); + ret = fg_read_regs(p, MAX17042_MODEL1, r_data0, ARRAY_SIZE(r_data0)); + if (ret) + goto check_model; + + ret = fg_read_regs(p, MAX17042_MODEL2, r_data1, ARRAY_SIZE(r_data1)); + if (ret) + goto check_model; + ret = fg_read_regs(p, MAX17042_MODEL3, r_data2, ARRAY_SIZE(r_data2)); if (ret) - printf("%s: Cell parameters read failed!\n", __func__); + goto check_model; for (i = 0; i < 16; i++) { if ((cell_character0[i] != r_data0[i]) @@ -98,29 +137,37 @@ rewrite_model: goto rewrite_model; } +lock_model: + if (!lock_count--) { + if (rewrite_count) + goto rewrite_model; + else + status_msg = "lock failed!"; + + goto error; + } + /* Lock model access */ pmic_reg_write(p, MAX17042_MLOCKReg1, MODEL_LOCK1); pmic_reg_write(p, MAX17042_MLOCKReg2, MODEL_LOCK2); /* Verify the model access is locked */ - ret |= fg_read_regs(p, MAX17042_MODEL1, r_data0, ARRAY_SIZE(r_data0)); - ret |= fg_read_regs(p, MAX17042_MODEL2, r_data1, ARRAY_SIZE(r_data1)); - ret |= fg_read_regs(p, MAX17042_MODEL3, r_data2, ARRAY_SIZE(r_data2)); + ret = fg_read_regs(p, MAX17042_MODEL1, r_data0, ARRAY_SIZE(r_data0)); + if (ret) + goto lock_model; - if (ret) { - printf("%s: Cell parameters read failed!\n", __func__); - return; - } + ret = fg_read_regs(p, MAX17042_MODEL2, r_data1, ARRAY_SIZE(r_data1)); + if (ret) + goto lock_model; + + ret = fg_read_regs(p, MAX17042_MODEL3, r_data2, ARRAY_SIZE(r_data2)); + if (ret) + goto lock_model; for (i = 0; i < ARRAY_SIZE(r_data0); i++) { /* Check if model locked */ - if (r_data0[i] || r_data1[i] || r_data2[i]) { - /* Rewrite model data - prevent from endless loop */ - if (rewrite_count--) { - puts("FG - Lock model access failed!\n"); - goto rewrite_model; - } - } + if (r_data0[i] || r_data1[i] || r_data2[i]) + goto lock_model; } /* Write Custom Parameters */ @@ -137,6 +184,11 @@ rewrite_model: /* Delay at least 350 ms */ mdelay(350); + + status_msg = "OK!"; +error: + debug("%s: model init status: %s\n", p->name, status_msg); + return; } static int power_update_battery(struct pmic *p, struct pmic *bat) @@ -178,7 +230,7 @@ static int power_check_battery(struct pmic *p, struct pmic *bat) ret |= pmic_reg_read(p, MAX17042_STATUS, &val); debug("fg status: 0x%x\n", val); - if (val == MAX17042_POR) + if (val & MAX17042_POR) por_fuelgauge_init(p); ret |= pmic_reg_read(p, MAX17042_VERSION, &val); -- 2.39.5