[PATCH v2] mtd: rawnand: stm32_fmc2: avoid warnings when building with W=1 option

From: Christophe Kerello
Date: Tue Jul 09 2019 - 05:42:53 EST


This patch solves warnings detected by setting W=1 when building.

Warnings type detected:
drivers/mtd/nand/raw/stm32_fmc2_nand.c: In function âstm32_fmc2_calc_timingsâ:
drivers/mtd/nand/raw/stm32_fmc2_nand.c:1417:23: warning: comparison is
always false due to limited range of data type [-Wtype-limits]
else if (tims->twait > FMC2_PMEM_PATT_TIMING_MASK)

Signed-off-by: Christophe Kerello <christophe.kerello@xxxxxx>
Cc: stable@xxxxxxxxxxxxxxx
Fixes: 2cd457f328c1 ("mtd: rawnand: stm32_fmc2: add STM32 FMC2 NAND flash
controller driver")
---
Changes in v2:
- Fixes/stable tag added

drivers/mtd/nand/raw/stm32_fmc2_nand.c | 90 +++++++++++-----------------------
1 file changed, 29 insertions(+), 61 deletions(-)

diff --git a/drivers/mtd/nand/raw/stm32_fmc2_nand.c b/drivers/mtd/nand/raw/stm32_fmc2_nand.c
index e63acc0..8cc852d 100644
--- a/drivers/mtd/nand/raw/stm32_fmc2_nand.c
+++ b/drivers/mtd/nand/raw/stm32_fmc2_nand.c
@@ -1427,21 +1427,16 @@ static void stm32_fmc2_calc_timings(struct nand_chip *chip,
struct stm32_fmc2_timings *tims = &nand->timings;
unsigned long hclk = clk_get_rate(fmc2->clk);
unsigned long hclkp = NSEC_PER_SEC / (hclk / 1000);
- int tar, tclr, thiz, twait, tset_mem, tset_att, thold_mem, thold_att;
-
- tar = hclkp;
- if (tar < sdrt->tAR_min)
- tar = sdrt->tAR_min;
- tims->tar = DIV_ROUND_UP(tar, hclkp) - 1;
- if (tims->tar > FMC2_PCR_TIMING_MASK)
- tims->tar = FMC2_PCR_TIMING_MASK;
-
- tclr = hclkp;
- if (tclr < sdrt->tCLR_min)
- tclr = sdrt->tCLR_min;
- tims->tclr = DIV_ROUND_UP(tclr, hclkp) - 1;
- if (tims->tclr > FMC2_PCR_TIMING_MASK)
- tims->tclr = FMC2_PCR_TIMING_MASK;
+ unsigned long timing, tar, tclr, thiz, twait;
+ unsigned long tset_mem, tset_att, thold_mem, thold_att;
+
+ tar = max_t(unsigned long, hclkp, sdrt->tAR_min);
+ timing = DIV_ROUND_UP(tar, hclkp) - 1;
+ tims->tar = min_t(unsigned long, timing, FMC2_PCR_TIMING_MASK);
+
+ tclr = max_t(unsigned long, hclkp, sdrt->tCLR_min);
+ timing = DIV_ROUND_UP(tclr, hclkp) - 1;
+ tims->tclr = min_t(unsigned long, timing, FMC2_PCR_TIMING_MASK);

tims->thiz = FMC2_THIZ;
thiz = (tims->thiz + 1) * hclkp;
@@ -1451,18 +1446,11 @@ static void stm32_fmc2_calc_timings(struct nand_chip *chip,
* tWAIT > tWP
* tWAIT > tREA + tIO
*/
- twait = hclkp;
- if (twait < sdrt->tRP_min)
- twait = sdrt->tRP_min;
- if (twait < sdrt->tWP_min)
- twait = sdrt->tWP_min;
- if (twait < sdrt->tREA_max + FMC2_TIO)
- twait = sdrt->tREA_max + FMC2_TIO;
- tims->twait = DIV_ROUND_UP(twait, hclkp);
- if (tims->twait == 0)
- tims->twait = 1;
- else if (tims->twait > FMC2_PMEM_PATT_TIMING_MASK)
- tims->twait = FMC2_PMEM_PATT_TIMING_MASK;
+ twait = max_t(unsigned long, hclkp, sdrt->tRP_min);
+ twait = max_t(unsigned long, twait, sdrt->tWP_min);
+ twait = max_t(unsigned long, twait, sdrt->tREA_max + FMC2_TIO);
+ timing = DIV_ROUND_UP(twait, hclkp);
+ tims->twait = clamp_val(timing, 1, FMC2_PMEM_PATT_TIMING_MASK);

/*
* tSETUP_MEM > tCS - tWAIT
@@ -1477,20 +1465,15 @@ static void stm32_fmc2_calc_timings(struct nand_chip *chip,
if (twait > thiz && (sdrt->tDS_min > twait - thiz) &&
(tset_mem < sdrt->tDS_min - (twait - thiz)))
tset_mem = sdrt->tDS_min - (twait - thiz);
- tims->tset_mem = DIV_ROUND_UP(tset_mem, hclkp);
- if (tims->tset_mem == 0)
- tims->tset_mem = 1;
- else if (tims->tset_mem > FMC2_PMEM_PATT_TIMING_MASK)
- tims->tset_mem = FMC2_PMEM_PATT_TIMING_MASK;
+ timing = DIV_ROUND_UP(tset_mem, hclkp);
+ tims->tset_mem = clamp_val(timing, 1, FMC2_PMEM_PATT_TIMING_MASK);

/*
* tHOLD_MEM > tCH
* tHOLD_MEM > tREH - tSETUP_MEM
* tHOLD_MEM > max(tRC, tWC) - (tSETUP_MEM + tWAIT)
*/
- thold_mem = hclkp;
- if (thold_mem < sdrt->tCH_min)
- thold_mem = sdrt->tCH_min;
+ thold_mem = max_t(unsigned long, hclkp, sdrt->tCH_min);
if (sdrt->tREH_min > tset_mem &&
(thold_mem < sdrt->tREH_min - tset_mem))
thold_mem = sdrt->tREH_min - tset_mem;
@@ -1500,11 +1483,8 @@ static void stm32_fmc2_calc_timings(struct nand_chip *chip,
if ((sdrt->tWC_min > tset_mem + twait) &&
(thold_mem < sdrt->tWC_min - (tset_mem + twait)))
thold_mem = sdrt->tWC_min - (tset_mem + twait);
- tims->thold_mem = DIV_ROUND_UP(thold_mem, hclkp);
- if (tims->thold_mem == 0)
- tims->thold_mem = 1;
- else if (tims->thold_mem > FMC2_PMEM_PATT_TIMING_MASK)
- tims->thold_mem = FMC2_PMEM_PATT_TIMING_MASK;
+ timing = DIV_ROUND_UP(thold_mem, hclkp);
+ tims->thold_mem = clamp_val(timing, 1, FMC2_PMEM_PATT_TIMING_MASK);

/*
* tSETUP_ATT > tCS - tWAIT
@@ -1526,11 +1506,8 @@ static void stm32_fmc2_calc_timings(struct nand_chip *chip,
if (twait > thiz && (sdrt->tDS_min > twait - thiz) &&
(tset_att < sdrt->tDS_min - (twait - thiz)))
tset_att = sdrt->tDS_min - (twait - thiz);
- tims->tset_att = DIV_ROUND_UP(tset_att, hclkp);
- if (tims->tset_att == 0)
- tims->tset_att = 1;
- else if (tims->tset_att > FMC2_PMEM_PATT_TIMING_MASK)
- tims->tset_att = FMC2_PMEM_PATT_TIMING_MASK;
+ timing = DIV_ROUND_UP(tset_att, hclkp);
+ tims->tset_att = clamp_val(timing, 1, FMC2_PMEM_PATT_TIMING_MASK);

/*
* tHOLD_ATT > tALH
@@ -1545,17 +1522,11 @@ static void stm32_fmc2_calc_timings(struct nand_chip *chip,
* tHOLD_ATT > tRC - (tSETUP_ATT + tWAIT)
* tHOLD_ATT > tWC - (tSETUP_ATT + tWAIT)
*/
- thold_att = hclkp;
- if (thold_att < sdrt->tALH_min)
- thold_att = sdrt->tALH_min;
- if (thold_att < sdrt->tCH_min)
- thold_att = sdrt->tCH_min;
- if (thold_att < sdrt->tCLH_min)
- thold_att = sdrt->tCLH_min;
- if (thold_att < sdrt->tCOH_min)
- thold_att = sdrt->tCOH_min;
- if (thold_att < sdrt->tDH_min)
- thold_att = sdrt->tDH_min;
+ thold_att = max_t(unsigned long, hclkp, sdrt->tALH_min);
+ thold_att = max_t(unsigned long, thold_att, sdrt->tCH_min);
+ thold_att = max_t(unsigned long, thold_att, sdrt->tCLH_min);
+ thold_att = max_t(unsigned long, thold_att, sdrt->tCOH_min);
+ thold_att = max_t(unsigned long, thold_att, sdrt->tDH_min);
if ((sdrt->tWB_max + FMC2_TIO + FMC2_TSYNC > tset_mem) &&
(thold_att < sdrt->tWB_max + FMC2_TIO + FMC2_TSYNC - tset_mem))
thold_att = sdrt->tWB_max + FMC2_TIO + FMC2_TSYNC - tset_mem;
@@ -1574,11 +1545,8 @@ static void stm32_fmc2_calc_timings(struct nand_chip *chip,
if ((sdrt->tWC_min > tset_att + twait) &&
(thold_att < sdrt->tWC_min - (tset_att + twait)))
thold_att = sdrt->tWC_min - (tset_att + twait);
- tims->thold_att = DIV_ROUND_UP(thold_att, hclkp);
- if (tims->thold_att == 0)
- tims->thold_att = 1;
- else if (tims->thold_att > FMC2_PMEM_PATT_TIMING_MASK)
- tims->thold_att = FMC2_PMEM_PATT_TIMING_MASK;
+ timing = DIV_ROUND_UP(thold_att, hclkp);
+ tims->thold_att = clamp_val(timing, 1, FMC2_PMEM_PATT_TIMING_MASK);
}

static int stm32_fmc2_setup_interface(struct nand_chip *chip, int chipnr,
--
1.9.1