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Date:   Sun, 25 Jul 2021 11:20:47 +0200
Message-Id: <e65dc96eb24caf8baa5431a51fe694b969e2d51f.1627204633.git.mirq-linux@rere.qmqm.pl>
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From:   =?UTF-8?q?Micha=C5=82=20Miros=C5=82aw?= <mirq-linux@rere.qmqm.pl>
Subject: [PATCH v4 2/5] mmc: sdhci: always obey programmable clock config in
 preset value
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To:     Kevin Liu <kliu5@marvell.com>,
        Michal Simek <michal.simek@xilinx.com>,
        Suneel Garapati <suneel.garapati@xilinx.com>,
        Ulf Hansson <ulf.hansson@linaro.org>
Cc:     Adrian Hunter <adrian.hunter@intel.com>, linux-mmc@vger.kernel.org,
        linux-kernel@vger.kernel.org, Al Cooper <alcooperx@gmail.com>
Precedence: bulk

When host controller uses programmable clock presets but doesn't
advertise programmable clock support, we can only guess what frequency
it generates. Let's at least return correct SDHCI_PROG_CLOCK_MODE bit
value in this case.

Fixes: 52983382c74f ("mmc: sdhci: enhance preset value function")
Signed-off-by: Michał Mirosław <mirq-linux@rere.qmqm.pl>
---
v4: no changes
v3: added a comment for this case
v2: no changes
---
 drivers/mmc/host/sdhci.c | 7 +++++--
 1 file changed, 5 insertions(+), 2 deletions(-)

diff --git a/drivers/mmc/host/sdhci.c b/drivers/mmc/host/sdhci.c
index c7438dd13e3e..3ab60e7f936b 100644
--- a/drivers/mmc/host/sdhci.c
+++ b/drivers/mmc/host/sdhci.c
@@ -1859,11 +1859,14 @@ u16 sdhci_calc_clk(struct sdhci_host *host, unsigned int clock,
 
 			pre_val = sdhci_get_preset_value(host);
 			div = FIELD_GET(SDHCI_PRESET_SDCLK_FREQ_MASK, pre_val);
-			if (host->clk_mul &&
-				(pre_val & SDHCI_PRESET_CLKGEN_SEL)) {
+			if (pre_val & SDHCI_PRESET_CLKGEN_SEL) {
 				clk = SDHCI_PROG_CLOCK_MODE;
 				real_div = div + 1;
 				clk_mul = host->clk_mul;
+				if (!clk_mul) {
+					/* The clock frequency is unknown. Assume undivided base. */
+					clk_mul = 1;
+				}
 			} else {
 				real_div = max_t(int, 1, div << 1);
 			}
-- 
2.30.2