Adding upstream version 4.19.249.upstream/4.19.249upstream

Signed-off-by: Daniel Baumann <daniel.baumann@progress-linux.org>

1 files changed, 134 insertions, 0 deletions

diff --git a/Documentation/devicetree/bindings/mmc/ti-omap-hsmmc.txt b/Documentation/devicetree/bindings/mmc/ti-omap-hsmmc.txt
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+* TI Highspeed MMC host controller for OMAP and 66AK2G family.
+
+The Highspeed MMC Host Controller on TI OMAP and 66AK2G family
+provides an interface for MMC, SD, and SDIO types of memory cards.
+
+This file documents differences between the core properties described
+by mmc.txt and the properties used by the omap_hsmmc driver.
+
+Required properties:
+--------------------
+- compatible:
+ Should be "ti,omap2-hsmmc", for OMAP2 controllers
+ Should be "ti,omap3-hsmmc", for OMAP3 controllers
+ Should be "ti,omap3-pre-es3-hsmmc" for OMAP3 controllers pre ES3.0
+ Should be "ti,omap4-hsmmc", for OMAP4 controllers
+ Should be "ti,am33xx-hsmmc", for AM335x controllers
+ Should be "ti,k2g-hsmmc", "ti,omap4-hsmmc" for 66AK2G controllers.
+
+SoC specific required properties:
+---------------------------------
+The following are mandatory properties for OMAPs, AM33xx and AM43xx SoCs only:
+- ti,hwmods: Must be "mmc<n>", n is controller instance starting 1.
+
+The following are mandatory properties for 66AK2G SoCs only:
+- power-domains:Should contain a phandle to a PM domain provider node
+		and an args specifier containing the MMC device id
+		value. This property is as per the binding,
+		Documentation/devicetree/bindings/soc/ti/sci-pm-domain.txt
+- clocks:	Must contain an entry for each entry in clock-names. Should
+		be defined as per the he appropriate clock bindings consumer
+		usage in Documentation/devicetree/bindings/clock/ti,sci-clk.txt
+- clock-names:	Shall be "fck" for the functional clock,
+		and "mmchsdb_fck" for the debounce clock.
+
+
+Optional properties:
+--------------------
+- ti,dual-volt:		boolean, supports dual voltage cards
+- <supply-name>-supply:	phandle to the regulator device tree node
+			  "supply-name" examples are "vmmc",
+			  "vmmc_aux"(deprecated)/"vqmmc" etc
+- ti,non-removable:	non-removable slot (like eMMC)
+- ti,needs-special-reset:	Requires a special softreset sequence
+- ti,needs-special-hs-handling:	HSMMC IP needs special setting
+				  for handling High Speed
+- dmas:			List of DMA specifiers with the controller specific
+			format as described in the generic DMA client
+			binding. A tx and rx specifier is required.
+- dma-names:		List of DMA request names. These strings correspond
+			1:1 with the DMA specifiers listed in dmas.
+			The string naming is to be "rx" and "tx" for
+			RX and TX DMA requests, respectively.
+
+Examples:
+
+[hwmod populated DMA resources]
+
+	mmc1: mmc@4809c000 {
+		compatible = "ti,omap4-hsmmc";
+		reg = <0x4809c000 0x400>;
+		ti,hwmods = "mmc1";
+		ti,dual-volt;
+		bus-width = <4>;
+		vmmc-supply = <&vmmc>; /* phandle to regulator node */
+		ti,non-removable;
+	};
+
+[generic DMA request binding]
+
+	mmc1: mmc@4809c000 {
+		compatible = "ti,omap4-hsmmc";
+		reg = <0x4809c000 0x400>;
+		ti,hwmods = "mmc1";
+		ti,dual-volt;
+		bus-width = <4>;
+		vmmc-supply = <&vmmc>; /* phandle to regulator node */
+		ti,non-removable;
+		dmas = <&edma 24
+			&edma 25>;
+		dma-names = "tx", "rx";
+	};
+
+[workaround for missing swakeup on am33xx]
+
+This SOC is missing the swakeup line, it will not detect SDIO irq
+while in suspend.
+
+                             ------
+                             | PRCM |
+                              ------
+                               ^ |
+                       swakeup | | fclk
+                               | v
+       ------                -------               -----
+      | card | -- CIRQ -->  | hsmmc | -- IRQ -->  | CPU |
+       ------                -------               -----
+
+In suspend the fclk is off and the module is disfunctional. Even register reads
+will fail. A small logic in the host will request fclk restore, when an
+external event is detected. Once the clock is restored, the host detects the
+event normally. Since am33xx doesn't have this line it never wakes from
+suspend.
+
+The workaround is to reconfigure the dat1 line as a GPIO upon suspend. To make
+this work, we need to set the named pinctrl states "default" and "idle".
+Prepare idle to remux dat1 as a gpio, and default to remux it back as sdio
+dat1. The MMC driver will then toggle between idle and default state during
+runtime.
+
+In summary:
+1. select matching 'compatible' section, see example below.
+2. specify pinctrl states "default" and "idle", "sleep" is optional.
+3. specify the gpio irq used for detecting sdio irq in suspend
+
+If configuration is incomplete, a warning message is emitted "falling back to
+polling". Also check the "sdio irq mode" in /sys/kernel/debug/mmc0/regs. Mind
+not every application needs SDIO irq, e.g. MMC cards.
+
+	mmc1: mmc@48060100 {
+		compatible = "ti,am33xx-hsmmc";
+		...
+		pinctrl-names = "default", "idle", "sleep"
+		pinctrl-0 = <&mmc1_pins>;
+		pinctrl-1 = <&mmc1_idle>;
+		pinctrl-2 = <&mmc1_sleep>;
+		...
+		interrupts-extended = <&intc 64 &gpio2 28 GPIO_ACTIVE_LOW>;
+	};
+
+	mmc1_idle : pinmux_cirq_pin {
+		pinctrl-single,pins = <
+		        0x0f8 0x3f      /* GPIO2_28 */
+		>;
+	};