Page MenuHomeFreeBSD
Files F177537501

D61023.1794660197.diff
No OneTemporary
Actions

Authored By
Unknown
Size
2 KB
Referenced Files
None
Subscribers
None

D61023.1794660197.diff
View Options

diff --git a/sys/dev/mmc/mmc_pwrseq.c b/sys/dev/mmc/mmc_pwrseq.c
--- a/sys/dev/mmc/mmc_pwrseq.c
+++ b/sys/dev/mmc/mmc_pwrseq.c
@@ -58,6 +58,7 @@
uint32_t post_power_on_delay_ms;
uint32_t power_off_delay_us;
+ bool powered;
};
static int
@@ -99,6 +100,23 @@
"Node have a clocks property but no clocks named \"ext_clock\"\n");
return (ENXIO);
}
+ /*
+ * The external clock is a free-running low-power
+ * oscillator (typically a PMIC 32kHz output) that the
+ * attached device needs for its whole lifetime. On
+ * several boards it is also shared with other users of
+ * the same module (e.g. the companion Bluetooth
+ * controller), so gating it from set_power() disturbs
+ * the other consumers. Enable it once here and leave
+ * it running rather than toggling it on every MMC
+ * power_mode transition.
+ */
+ rv = clk_enable(sc->ext_clock);
+ if (rv != 0) {
+ device_printf(dev,
+ "Cannot enable \"ext_clock\"\n");
+ return (ENXIO);
+ }
}
OF_getencprop(node, "post-power-on-delay-ms", &sc->post_power_on_delay_ms, sizeof(uint32_t));
OF_getencprop(node, "power-off-delay-us", &sc->power_off_delay_us, sizeof(uint32_t));
@@ -133,13 +151,17 @@
sc = device_get_softc(dev);
- if (power_on) {
- if (sc->ext_clock) {
- rv = clk_enable(sc->ext_clock);
- if (rv != 0)
- return (rv);
- }
+ /*
+ * set_power() is driven from the MMC power_mode IOS and can be
+ * called repeatedly for the same state during probing and tuning.
+ * Only act on real transitions. The external clock is handled once
+ * at attach (see mmc_pwrseq_attach()); here we only drive the reset
+ * line, which is what actually sequences the device's power.
+ */
+ if (power_on == sc->powered)
+ return (0);
+ if (power_on) {
if (sc->reset_gpio) {
rv = gpio_pin_set_active(sc->reset_gpio, false);
if (rv != 0)
@@ -155,15 +177,11 @@
return (rv);
}
- if (sc->ext_clock) {
- rv = clk_stop(sc->ext_clock);
- if (rv != 0)
- return (rv);
- }
if (sc->power_off_delay_us)
DELAY(sc->power_off_delay_us);
}
+ sc->powered = power_on;
return (0);
}

File Metadata

Mime Type
text/plain
Expires
Sat, Nov 14, 12:43 PM (8 h, 23 m)
Storage Engine
blob
Storage Format
Raw Data
Storage Handle
41257042
Default Alt Text
D61023.1794660197.diff (2 KB)

Event Timeline