[PATCH AUTOSEL for 4.15 72/78] clk: at91: pmc: Wait for clocks when resuming

[Sasha Levin]

From: Romain Izard <romain.izard....@gmail.com>

[ Upstream commit 960e1c4d93be86d3b118fe22d4edc69e401b28b5 ]

Wait for the syncronization of all clocks when resuming, not only the
UPLL clock. Do not use regmap_read_poll_timeout, as it will call BUG()
when interrupts are masked, which is the case in here.

Signed-off-by: Romain Izard <romain.izard....@gmail.com>
Acked-by: Ludovic Desroches <ludovic.desroc...@microchip.com>
Acked-by: Nicolas Ferre <nicolas.fe...@microchip.com>
Acked-by: Alexandre Belloni <alexandre.bell...@free-electrons.com>
Signed-off-by: Stephen Boyd <sb...@codeaurora.org>
Signed-off-by: Sasha Levin <alexander.le...@microsoft.com>
---
 drivers/clk/at91/pmc.c | 24 ++++++++++++++++--------
 1 file changed, 16 insertions(+), 8 deletions(-)

diff --git a/drivers/clk/at91/pmc.c b/drivers/clk/at91/pmc.c
index 775af473fe11..5c2b26de303e 100644
--- a/drivers/clk/at91/pmc.c
+++ b/drivers/clk/at91/pmc.c
@@ -107,10 +107,20 @@ static int pmc_suspend(void)
        return 0;
 }
 
+static bool pmc_ready(unsigned int mask)
+{
+       unsigned int status;
+
+       regmap_read(pmcreg, AT91_PMC_SR, &status);
+
+       return ((status & mask) == mask) ? 1 : 0;
+}
+
 static void pmc_resume(void)
 {
-       int i, ret = 0;
+       int i;
        u32 tmp;
+       u32 mask = AT91_PMC_MCKRDY | AT91_PMC_LOCKA;
 
        regmap_read(pmcreg, AT91_PMC_MCKR, &tmp);
        if (pmc_cache.mckr != tmp)
@@ -134,13 +144,11 @@ static void pmc_resume(void)
                             AT91_PMC_PCR_CMD);
        }
 
-       if (pmc_cache.uckr & AT91_PMC_UPLLEN) {
-               ret = regmap_read_poll_timeout(pmcreg, AT91_PMC_SR, tmp,
-                                              !(tmp & AT91_PMC_LOCKU),
-                                              10, 5000);
-               if (ret)
-                       pr_crit("USB PLL didn't lock when resuming\n");
-       }
+       if (pmc_cache.uckr & AT91_PMC_UPLLEN)
+               mask |= AT91_PMC_LOCKU;
+
+       while (!pmc_ready(mask))
+               cpu_relax();
 }
 
 static struct syscore_ops pmc_syscore_ops = {
-- 
2.14.1