memory: stm32-fmc2-ebi: check regmap_read return value

Check regmap_read return value to avoid to use uninitialized local
variables.

Signed-off-by: Christophe Kerello <christophe.kerello@foss.st.com>
Link: https://lore.kernel.org/r/20240226101428.37791-3-christophe.kerello@foss.st.com
Signed-off-by: Krzysztof Kozlowski <krzysztof.kozlowski@linaro.org>

diff --git a/drivers/memory/stm32-fmc2-ebi.c b/drivers/memory/stm32-fmc2-ebi.c
index 47d0ea5f16168461eaebdd842884e0cca0636ba8..81c1cd88fb976814dff7f87532598ebf9d3c87d2 100644 (file)
--- a/drivers/memory/stm32-fmc2-ebi.c
+++ b/drivers/memory/stm32-fmc2-ebi.c
@@ -181,8 +181,11 @@ static int stm32_fmc2_ebi_check_mux(struct stm32_fmc2_ebi *ebi,
                                    int cs)
 {
        u32 bcr;
+       int ret;
 
-       regmap_read(ebi->regmap, FMC2_BCR(cs), &bcr);
+       ret = regmap_read(ebi->regmap, FMC2_BCR(cs), &bcr);
+       if (ret)
+               return ret;
 
        if (bcr & FMC2_BCR_MTYP)
                return 0;
@@ -195,8 +198,11 @@ static int stm32_fmc2_ebi_check_waitcfg(struct stm32_fmc2_ebi *ebi,
                                        int cs)
 {
        u32 bcr, val = FIELD_PREP(FMC2_BCR_MTYP, FMC2_BCR_MTYP_NOR);
+       int ret;
 
-       regmap_read(ebi->regmap, FMC2_BCR(cs), &bcr);
+       ret = regmap_read(ebi->regmap, FMC2_BCR(cs), &bcr);
+       if (ret)
+               return ret;
 
        if ((bcr & FMC2_BCR_MTYP) == val && bcr & FMC2_BCR_BURSTEN)
                return 0;
@@ -209,8 +215,11 @@ static int stm32_fmc2_ebi_check_sync_trans(struct stm32_fmc2_ebi *ebi,
                                           int cs)
 {
        u32 bcr;
+       int ret;
 
-       regmap_read(ebi->regmap, FMC2_BCR(cs), &bcr);
+       ret = regmap_read(ebi->regmap, FMC2_BCR(cs), &bcr);
+       if (ret)
+               return ret;
 
        if (bcr & FMC2_BCR_BURSTEN)
                return 0;
@@ -223,8 +232,11 @@ static int stm32_fmc2_ebi_check_async_trans(struct stm32_fmc2_ebi *ebi,
                                            int cs)
 {
        u32 bcr;
+       int ret;
 
-       regmap_read(ebi->regmap, FMC2_BCR(cs), &bcr);
+       ret = regmap_read(ebi->regmap, FMC2_BCR(cs), &bcr);
+       if (ret)
+               return ret;
 
        if (!(bcr & FMC2_BCR_BURSTEN) || !(bcr & FMC2_BCR_CBURSTRW))
                return 0;
@@ -237,8 +249,11 @@ static int stm32_fmc2_ebi_check_cpsize(struct stm32_fmc2_ebi *ebi,
                                       int cs)
 {
        u32 bcr, val = FIELD_PREP(FMC2_BCR_MTYP, FMC2_BCR_MTYP_PSRAM);
+       int ret;
 
-       regmap_read(ebi->regmap, FMC2_BCR(cs), &bcr);
+       ret = regmap_read(ebi->regmap, FMC2_BCR(cs), &bcr);
+       if (ret)
+               return ret;
 
        if ((bcr & FMC2_BCR_MTYP) == val && bcr & FMC2_BCR_BURSTEN)
                return 0;
@@ -251,12 +266,18 @@ static int stm32_fmc2_ebi_check_address_hold(struct stm32_fmc2_ebi *ebi,
                                             int cs)
 {
        u32 bcr, bxtr, val = FIELD_PREP(FMC2_BXTR_ACCMOD, FMC2_BXTR_EXTMOD_D);
+       int ret;
+
+       ret = regmap_read(ebi->regmap, FMC2_BCR(cs), &bcr);
+       if (ret)
+               return ret;
 
-       regmap_read(ebi->regmap, FMC2_BCR(cs), &bcr);
        if (prop->reg_type == FMC2_REG_BWTR)
-               regmap_read(ebi->regmap, FMC2_BWTR(cs), &bxtr);
+               ret = regmap_read(ebi->regmap, FMC2_BWTR(cs), &bxtr);
        else
-               regmap_read(ebi->regmap, FMC2_BTR(cs), &bxtr);
+               ret = regmap_read(ebi->regmap, FMC2_BTR(cs), &bxtr);
+       if (ret)
+               return ret;
 
        if ((!(bcr & FMC2_BCR_BURSTEN) || !(bcr & FMC2_BCR_CBURSTRW)) &&
            ((bxtr & FMC2_BXTR_ACCMOD) == val || bcr & FMC2_BCR_MUXEN))
@@ -270,12 +291,19 @@ static int stm32_fmc2_ebi_check_clk_period(struct stm32_fmc2_ebi *ebi,
                                           int cs)
 {
        u32 bcr, bcr1;
+       int ret;
 
-       regmap_read(ebi->regmap, FMC2_BCR(cs), &bcr);
-       if (cs)
-               regmap_read(ebi->regmap, FMC2_BCR1, &bcr1);
-       else
+       ret = regmap_read(ebi->regmap, FMC2_BCR(cs), &bcr);
+       if (ret)
+               return ret;
+
+       if (cs) {
+               ret = regmap_read(ebi->regmap, FMC2_BCR1, &bcr1);
+               if (ret)
+                       return ret;
+       } else {
                bcr1 = bcr;
+       }
 
        if (bcr & FMC2_BCR_BURSTEN && (!cs || !(bcr1 & FMC2_BCR1_CCLKEN)))
                return 0;
@@ -307,12 +335,18 @@ static u32 stm32_fmc2_ebi_ns_to_clk_period(struct stm32_fmc2_ebi *ebi,
 {
        u32 nb_clk_cycles = stm32_fmc2_ebi_ns_to_clock_cycles(ebi, cs, setup);
        u32 bcr, btr, clk_period;
+       int ret;
+
+       ret = regmap_read(ebi->regmap, FMC2_BCR1, &bcr);
+       if (ret)
+               return ret;
 
-       regmap_read(ebi->regmap, FMC2_BCR1, &bcr);
        if (bcr & FMC2_BCR1_CCLKEN || !cs)
-               regmap_read(ebi->regmap, FMC2_BTR1, &btr);
+               ret = regmap_read(ebi->regmap, FMC2_BTR1, &btr);
        else
-               regmap_read(ebi->regmap, FMC2_BTR(cs), &btr);
+               ret = regmap_read(ebi->regmap, FMC2_BTR(cs), &btr);
+       if (ret)
+               return ret;
 
        clk_period = FIELD_GET(FMC2_BTR_CLKDIV, btr) + 1;
 
@@ -571,11 +605,16 @@ static int stm32_fmc2_ebi_set_address_setup(struct stm32_fmc2_ebi *ebi,
        if (ret)
                return ret;
 
-       regmap_read(ebi->regmap, FMC2_BCR(cs), &bcr);
+       ret = regmap_read(ebi->regmap, FMC2_BCR(cs), &bcr);
+       if (ret)
+               return ret;
+
        if (prop->reg_type == FMC2_REG_BWTR)
-               regmap_read(ebi->regmap, FMC2_BWTR(cs), &bxtr);
+               ret = regmap_read(ebi->regmap, FMC2_BWTR(cs), &bxtr);
        else
-               regmap_read(ebi->regmap, FMC2_BTR(cs), &bxtr);
+               ret = regmap_read(ebi->regmap, FMC2_BTR(cs), &bxtr);
+       if (ret)
+               return ret;
 
        if ((bxtr & FMC2_BXTR_ACCMOD) == val || bcr & FMC2_BCR_MUXEN)
                val = clamp_val(setup, 1, FMC2_BXTR_ADDSET_MAX);
@@ -693,11 +732,14 @@ static int stm32_fmc2_ebi_set_max_low_pulse(struct stm32_fmc2_ebi *ebi,
                                            int cs, u32 setup)
 {
        u32 old_val, new_val, pcscntr;
+       int ret;
 
        if (setup < 1)
                return 0;
 
-       regmap_read(ebi->regmap, FMC2_PCSCNTR, &pcscntr);
+       ret = regmap_read(ebi->regmap, FMC2_PCSCNTR, &pcscntr);
+       if (ret)
+               return ret;
 
        /* Enable counter for the bank */
        regmap_update_bits(ebi->regmap, FMC2_PCSCNTR,
@@ -944,17 +986,20 @@ static void stm32_fmc2_ebi_disable_bank(struct stm32_fmc2_ebi *ebi, int cs)
        regmap_update_bits(ebi->regmap, FMC2_BCR(cs), FMC2_BCR_MBKEN, 0);
 }
 
-static void stm32_fmc2_ebi_save_setup(struct stm32_fmc2_ebi *ebi)
+static int stm32_fmc2_ebi_save_setup(struct stm32_fmc2_ebi *ebi)
 {
        unsigned int cs;
+       int ret;
 
        for (cs = 0; cs < FMC2_MAX_EBI_CE; cs++) {
-               regmap_read(ebi->regmap, FMC2_BCR(cs), &ebi->bcr[cs]);
-               regmap_read(ebi->regmap, FMC2_BTR(cs), &ebi->btr[cs]);
-               regmap_read(ebi->regmap, FMC2_BWTR(cs), &ebi->bwtr[cs]);
+               ret = regmap_read(ebi->regmap, FMC2_BCR(cs), &ebi->bcr[cs]);
+               ret |= regmap_read(ebi->regmap, FMC2_BTR(cs), &ebi->btr[cs]);
+               ret |= regmap_read(ebi->regmap, FMC2_BWTR(cs), &ebi->bwtr[cs]);
+               if (ret)
+                       return ret;
        }
 
-       regmap_read(ebi->regmap, FMC2_PCSCNTR, &ebi->pcscntr);
+       return regmap_read(ebi->regmap, FMC2_PCSCNTR, &ebi->pcscntr);
 }
 
 static void stm32_fmc2_ebi_set_setup(struct stm32_fmc2_ebi *ebi)
@@ -983,22 +1028,29 @@ static void stm32_fmc2_ebi_disable_banks(struct stm32_fmc2_ebi *ebi)
 }
 
 /* NWAIT signal can not be connected to EBI controller and NAND controller */
-static bool stm32_fmc2_ebi_nwait_used_by_ctrls(struct stm32_fmc2_ebi *ebi)
+static int stm32_fmc2_ebi_nwait_used_by_ctrls(struct stm32_fmc2_ebi *ebi)
 {
+       struct device *dev = ebi->dev;
        unsigned int cs;
        u32 bcr;
+       int ret;
 
        for (cs = 0; cs < FMC2_MAX_EBI_CE; cs++) {
                if (!(ebi->bank_assigned & BIT(cs)))
                        continue;
 
-               regmap_read(ebi->regmap, FMC2_BCR(cs), &bcr);
+               ret = regmap_read(ebi->regmap, FMC2_BCR(cs), &bcr);
+               if (ret)
+                       return ret;
+
                if ((bcr & FMC2_BCR_WAITEN || bcr & FMC2_BCR_ASYNCWAIT) &&
-                   ebi->bank_assigned & BIT(FMC2_NAND))
-                       return true;
+                   ebi->bank_assigned & BIT(FMC2_NAND)) {
+                       dev_err(dev, "NWAIT signal connected to EBI and NAND controllers\n");
+                       return -EINVAL;
+               }
        }
 
-       return false;
+       return 0;
 }
 
 static void stm32_fmc2_ebi_enable(struct stm32_fmc2_ebi *ebi)
@@ -1085,10 +1137,9 @@ static int stm32_fmc2_ebi_parse_dt(struct stm32_fmc2_ebi *ebi)
                return -ENODEV;
        }
 
-       if (stm32_fmc2_ebi_nwait_used_by_ctrls(ebi)) {
-               dev_err(dev, "NWAIT signal connected to EBI and NAND controllers\n");
-               return -EINVAL;
-       }
+       ret = stm32_fmc2_ebi_nwait_used_by_ctrls(ebi);
+       if (ret)
+               return ret;
 
        stm32_fmc2_ebi_enable(ebi);
 
@@ -1133,7 +1184,10 @@ static int stm32_fmc2_ebi_probe(struct platform_device *pdev)
        if (ret)
                goto err_release;
 
-       stm32_fmc2_ebi_save_setup(ebi);
+       ret = stm32_fmc2_ebi_save_setup(ebi);
+       if (ret)
+               goto err_release;
+
        platform_set_drvdata(pdev, ebi);
 
        return 0;