releases/3.14.44/mmc-atmel-mci-fix-bad-variable-type-for-clkdiv.patch

   1 From 60c8f783a18feb95ad967c87e9660caf09fb4700 Mon Sep 17 00:00:00 2001
   2 From: Ludovic Desroches <ludovic.desroches@atmel.com>
   3 Date: Wed, 6 May 2015 15:16:46 +0200
   4 Subject: mmc: atmel-mci: fix bad variable type for clkdiv
   5
   6 From: Ludovic Desroches <ludovic.desroches@atmel.com>
   7
   8 commit 60c8f783a18feb95ad967c87e9660caf09fb4700 upstream.
   9
  10 clkdiv is declared as an u32 but it can be set to a negative value
  11 causing a huge divisor value. Change its type to int to avoid this case.
  12
  13 Signed-off-by: Ludovic Desroches <ludovic.desroches@atmel.com>
  14 Signed-off-by: Ulf Hansson <ulf.hansson@linaro.org>
  15 Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
  16
  17 ---
  18  drivers/mmc/host/atmel-mci.c |    9 +++++++--
  19  1 file changed, 7 insertions(+), 2 deletions(-)
  20
  21 --- a/drivers/mmc/host/atmel-mci.c
  22 +++ b/drivers/mmc/host/atmel-mci.c
  23 @@ -1300,7 +1300,7 @@ static void atmci_set_ios(struct mmc_hos
  24
  25         if (ios->clock) {
  26                 unsigned int clock_min = ~0U;
  27 -               u32 clkdiv;
  28 +               int clkdiv;
  29
  30                 clk_prepare(host->mck);
  31                 unprepare_clk = true;
  32 @@ -1329,7 +1329,12 @@ static void atmci_set_ios(struct mmc_hos
  33                 /* Calculate clock divider */
  34                 if (host->caps.has_odd_clk_div) {
  35                         clkdiv = DIV_ROUND_UP(host->bus_hz, clock_min) - 2;
  36 -                       if (clkdiv > 511) {
  37 +                       if (clkdiv < 0) {
  38 +                               dev_warn(&mmc->class_dev,
  39 +                                        "clock %u too fast; using %lu\n",
  40 +                                        clock_min, host->bus_hz / 2);
  41 +                               clkdiv = 0;
  42 +                       } else if (clkdiv > 511) {
  43                                 dev_warn(&mmc->class_dev,
  44                                          "clock %u too slow; using %lu\n",
  45                                          clock_min, host->bus_hz / (511 + 2));