SDHC interface

SDHC interface. More...

Data Structures
struct	sdhc_command
	SD host controller command structure. More...
struct	sdhc_data
	SD host controller data structure. More...
struct	sdhc_host_caps
	SD host controller capabilities. More...
struct	sdhc_io
	SD host controller I/O control structure. More...
struct	sdhc_host_props
	SD host controller properties. More...
struct	sdhc_driver_api

Macros
#define	SDHC_NATIVE_RESPONSE_MASK   0xF
#define	SDHC_SPI_RESPONSE_TYPE_MASK   0xF0

Typedefs
typedef void(*	sdhc_interrupt_cb_t) (const struct device *dev, int reason, const void *user_data)
	SDHC card interrupt callback prototype.

Enumerations
enum	sdhc_bus_mode { SDHC_BUSMODE_OPENDRAIN = 1 , SDHC_BUSMODE_PUSHPULL = 2 }
	SD bus mode. More...
enum	sdhc_power { SDHC_POWER_OFF = 1 , SDHC_POWER_ON = 2 }
	SD host controller power. More...
enum	sdhc_bus_width { SDHC_BUS_WIDTH1BIT = 1U , SDHC_BUS_WIDTH4BIT = 4U , SDHC_BUS_WIDTH8BIT = 8U }
	SD host controller bus width. More...
enum	sdhc_timing_mode {   SDHC_TIMING_LEGACY = 1U , SDHC_TIMING_HS = 2U , SDHC_TIMING_SDR12 = 3U , SDHC_TIMING_SDR25 = 4U ,   SDHC_TIMING_SDR50 = 5U , SDHC_TIMING_SDR104 = 6U , SDHC_TIMING_DDR50 = 7U , SDHC_TIMING_DDR52 = 8U ,   SDHC_TIMING_HS200 = 9U , SDHC_TIMING_HS400 = 10U }
	SD host controller timing mode. More...
enum	sd_voltage { SD_VOL_3_3_V = 1U , SD_VOL_3_0_V = 2U , SD_VOL_1_8_V = 3U , SD_VOL_1_2_V = 4U }
	SD voltage. More...
enum	sdhc_interrupt_source { SDHC_INT_SDIO = BIT(0) , SDHC_INT_INSERTED = BIT(1) , SDHC_INT_REMOVED = BIT(2) }
	SD host controller interrupt sources. More...

Functions
int	sdhc_hw_reset (const struct device *dev)
	reset SDHC controller state
int	sdhc_request (const struct device *dev, struct sdhc_command *cmd, struct sdhc_data *data)
	Send command to SDHC.
int	sdhc_set_io (const struct device *dev, struct sdhc_io *io)
	set I/O properties of SDHC
int	sdhc_card_present (const struct device *dev)
	check for SDHC card presence
int	sdhc_execute_tuning (const struct device *dev)
	run SDHC tuning
int	sdhc_card_busy (const struct device *dev)
	check if SD card is busy
int	sdhc_get_host_props (const struct device *dev, struct sdhc_host_props *props)
	Get SD host controller properties.
int	sdhc_enable_interrupt (const struct device *dev, sdhc_interrupt_cb_t callback, int sources, void *user_data)
	Enable SDHC interrupt sources.
int	sdhc_disable_interrupt (const struct device *dev, int sources)
	Disable SDHC interrupt sources.

SD command timeouts
#define	SDHC_TIMEOUT_FOREVER   (-1)

Detailed Description

SDHC interface.

Since

3.1

Version

0.1.0

Macro Definition Documentation

SDHC_NATIVE_RESPONSE_MASK

#define SDHC_NATIVE_RESPONSE_MASK   0xF

#include <zephyr/drivers/sdhc.h>

SDHC_SPI_RESPONSE_TYPE_MASK

#define SDHC_SPI_RESPONSE_TYPE_MASK   0xF0

#include <zephyr/drivers/sdhc.h>

SDHC_TIMEOUT_FOREVER

#define SDHC_TIMEOUT_FOREVER   (-1)

#include <zephyr/drivers/sdhc.h>

Typedef Documentation

sdhc_interrupt_cb_t

sdhc_interrupt_cb_t

#include <zephyr/drivers/sdhc.h>

SDHC card interrupt callback prototype.

Function prototype for SDHC card interrupt callback.

Parameters

dev	SDHC device that produced interrupt
reason	one of sdhc_interrupt_source values.
user_data	User data, set via sdhc_enable_interrupt

Enumeration Type Documentation

sd_voltage

enum sd_voltage

#include <zephyr/drivers/sdhc.h>

SD voltage.

UHS cards can run with 1.8V signalling for improved power consumption. Legacy cards may support 3.0V signalling, and all cards start at 3.3V. Only relevant for SD controllers, not SPI ones.

Enumerator
SD_VOL_3_3_V	card operation voltage around 3.3v
SD_VOL_3_0_V	card operation voltage around 3.0v
SD_VOL_1_8_V	card operation voltage around 1.8v
SD_VOL_1_2_V	card operation voltage around 1.2v

sdhc_bus_mode

enum sdhc_bus_mode

#include <zephyr/drivers/sdhc.h>

SD bus mode.

Most controllers will use push/pull, including spi, but SDHC controllers that implement SD host specification can support open drain mode

Enumerator
SDHC_BUSMODE_OPENDRAIN
SDHC_BUSMODE_PUSHPULL

sdhc_bus_width

enum sdhc_bus_width

#include <zephyr/drivers/sdhc.h>

SD host controller bus width.

Only relevant in SD mode, SPI does not support bus width. UHS cards will use 4 bit data bus, all cards start in 1 bit mode

Enumerator
SDHC_BUS_WIDTH1BIT
SDHC_BUS_WIDTH4BIT
SDHC_BUS_WIDTH8BIT

sdhc_interrupt_source

enum sdhc_interrupt_source

#include <zephyr/drivers/sdhc.h>

SD host controller interrupt sources.

Interrupt sources for SD host controller.

Enumerator
SDHC_INT_SDIO	Card interrupt, used by SDIO cards.
SDHC_INT_INSERTED	Card was inserted into slot.
SDHC_INT_REMOVED	Card was removed from slot.

sdhc_power

enum sdhc_power

#include <zephyr/drivers/sdhc.h>

SD host controller power.

Many host controllers can control power to attached SD cards. This enum allows applications to request the host controller power off the SD card.

Enumerator
SDHC_POWER_OFF
SDHC_POWER_ON

sdhc_timing_mode

enum sdhc_timing_mode

#include <zephyr/drivers/sdhc.h>

SD host controller timing mode.

Used by SD host controller to determine the timing of the cards attached to the bus. Cards start with legacy timing, but UHS-II cards can go up to SDR104.

Enumerator
SDHC_TIMING_LEGACY	Legacy 3.3V Mode.
SDHC_TIMING_HS	Legacy High speed mode (3.3V)
SDHC_TIMING_SDR12	Identification mode & SDR12.
SDHC_TIMING_SDR25	High speed mode & SDR25.
SDHC_TIMING_SDR50	SDR49 mode.
SDHC_TIMING_SDR104	SDR104 mode.
SDHC_TIMING_DDR50	DDR50 mode.
SDHC_TIMING_DDR52	DDR52 mode.
SDHC_TIMING_HS200	HS200 mode.
SDHC_TIMING_HS400	HS400 mode.

Function Documentation

sdhc_card_busy()

int sdhc_card_busy

(

const struct device *

dev

)

#include <zephyr/drivers/sdhc.h>

check if SD card is busy

This check should generally be implemented as checking the line level of the DAT[0:3] lines of the SD bus. No SD commands need to be sent, the controller simply needs to report the status of the SD bus.

Parameters

dev	SDHC device

Return values

0	card is not busy
1	card is busy
-EIO	I/O error

sdhc_card_present()

int sdhc_card_present

(

const struct device *

dev

)

#include <zephyr/drivers/sdhc.h>

check for SDHC card presence

Checks if card is present on the SD bus. Note that if a controller requires cards be powered up to detect presence, it should do so in this function.

Parameters

dev	SDHC device

Return values

1	card is present
0	card is not present
-EIO	I/O error

sdhc_disable_interrupt()

int sdhc_disable_interrupt	(	const struct device *	dev,
		int	sources
	)

#include <zephyr/drivers/sdhc.h>

Disable SDHC interrupt sources.

Disables SDHC interrupt sources. If multiple sources are enabled, only the ones specified in "sources" will be masked.

Parameters

dev	SDHC device
sources	bitmask of sdhc_interrupt_source values indicating which interrupts should be disabled.

Return values

0	interrupts were disabled
-ENOTSUP	controller does not support this function
-EIO	I/O error

sdhc_enable_interrupt()

int sdhc_enable_interrupt	(	const struct device *	dev,
		sdhc_interrupt_cb_t	callback,
		int	sources,
		void *	user_data
	)

#include <zephyr/drivers/sdhc.h>

Enable SDHC interrupt sources.

Enables SDHC interrupt sources. Each subsequent call of this function should replace the previous callback set, and leave only the interrupts specified in the "sources" argument enabled.

Parameters

dev	SDHC device
callback	Callback called when interrupt occurs
sources	bitmask of sdhc_interrupt_source values indicating which interrupts should produce a callback
user_data	parameter that will be passed to callback function

Return values

0	interrupts were enabled, and callback was installed
-ENOTSUP	controller does not support this function
-EIO	I/O error

sdhc_execute_tuning()

int sdhc_execute_tuning

(

const struct device *

dev

)

#include <zephyr/drivers/sdhc.h>

run SDHC tuning

SD cards require signal tuning for UHS modes SDR104 and SDR50. This function allows an application to request the SD host controller to tune the card.

Parameters

dev	SDHC device

Return values

0	tuning succeeded, card is ready for commands
-ETIMEDOUT	tuning failed after timeout
-ENOTSUP	controller does not support tuning
-EIO	I/O error while tuning

sdhc_get_host_props()

int sdhc_get_host_props	(	const struct device *	dev,
		struct sdhc_host_props *	props
	)

#include <zephyr/drivers/sdhc.h>

Get SD host controller properties.

Gets host properties from the host controller. Host controller should initialize all values in the sdhc_host_props structure provided.

Parameters

dev	SDHC device
props	property structure to be filled by sdhc driver

Return values

0	function succeeded.
-ENOTSUP	host controller does not support this call

sdhc_hw_reset()

int sdhc_hw_reset

(

const struct device *

dev

)

#include <zephyr/drivers/sdhc.h>

reset SDHC controller state

Used when the SDHC has encountered an error. Resetting the SDHC controller should clear all errors on the SDHC, but does not necessarily reset I/O settings to boot (this can be done with sdhc_set_io)

Parameters

dev	SD host controller device

Return values

0	reset succeeded
-ETIMEDOUT	controller reset timed out
-EIO	reset failed

sdhc_request()

int sdhc_request	(	const struct device *	dev,
		struct sdhc_command *	cmd,
		struct sdhc_data *	data
	)

#include <zephyr/drivers/sdhc.h>

Send command to SDHC.

Sends a command to the SD host controller, which will send this command to attached SD cards.

Parameters

dev	SDHC device
cmd	SDHC command
data	SDHC data. Leave NULL to send SD command without data.

Return values

0	command was sent successfully
-ETIMEDOUT	command timed out while sending
-ENOTSUP	host controller does not support command
-EIO	I/O error

sdhc_set_io()

int sdhc_set_io	(	const struct device *	dev,
		struct sdhc_io *	io
	)

#include <zephyr/drivers/sdhc.h>

set I/O properties of SDHC

I/O properties should be reconfigured when the card has been sent a command to change its own SD settings. This function can also be used to toggle power to the SD card.

Parameters

dev	SDHC device
io	I/O properties

Returns

0 I/O was configured correctly

-ENOTSUP controller does not support these I/O settings

-EIO controller could not configure I/O settings