Merge branches 'topic/core', 'topic/slave' and 'fix/doc' of git://git.kernel.org/pub/scm/linux/kernel/git/broonie/spi into spi-master
This commit is contained in:
Mark Brown
commit
c94085f587
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|
@ -1,17 +1,23 @@
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|||
SPI (Serial Peripheral Interface) busses
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SPI busses can be described with a node for the SPI master device
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and a set of child nodes for each SPI slave on the bus. For this
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discussion, it is assumed that the system's SPI controller is in
|
||||
SPI master mode. This binding does not describe SPI controllers
|
||||
in slave mode.
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SPI busses can be described with a node for the SPI controller device
|
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and a set of child nodes for each SPI slave on the bus. The system's SPI
|
||||
controller may be described for use in SPI master mode or in SPI slave mode,
|
||||
but not for both at the same time.
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|
||||
The SPI master node requires the following properties:
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The SPI controller node requires the following properties:
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- compatible - Name of SPI bus controller following generic names
|
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recommended practice.
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|
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In master mode, the SPI controller node requires the following additional
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properties:
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- #address-cells - number of cells required to define a chip select
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address on the SPI bus.
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- #size-cells - should be zero.
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- compatible - name of SPI bus controller following generic names
|
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recommended practice.
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|
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In slave mode, the SPI controller node requires one additional property:
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- spi-slave - Empty property.
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No other properties are required in the SPI bus node. It is assumed
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that a driver for an SPI bus device will understand that it is an SPI bus.
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However, the binding does not attempt to define the specific method for
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|
|
@ -21,7 +27,7 @@ assumption that board specific platform code will be used to manage
|
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chip selects. Individual drivers can define additional properties to
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support describing the chip select layout.
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Optional properties:
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Optional properties (master mode only):
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- cs-gpios - gpios chip select.
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- num-cs - total number of chipselects.
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|
|
@ -41,28 +47,36 @@ cs1 : native
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cs2 : &gpio1 1 0
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cs3 : &gpio1 2 0
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SPI slave nodes must be children of the SPI master node and can
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contain the following properties.
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- reg - (required) chip select address of device.
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- compatible - (required) name of SPI device following generic names
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recommended practice.
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- spi-max-frequency - (required) Maximum SPI clocking speed of device in Hz.
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- spi-cpol - (optional) Empty property indicating device requires
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inverse clock polarity (CPOL) mode.
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- spi-cpha - (optional) Empty property indicating device requires
|
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shifted clock phase (CPHA) mode.
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- spi-cs-high - (optional) Empty property indicating device requires
|
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chip select active high.
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- spi-3wire - (optional) Empty property indicating device requires
|
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3-wire mode.
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- spi-lsb-first - (optional) Empty property indicating device requires
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LSB first mode.
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- spi-tx-bus-width - (optional) The bus width (number of data wires) that is
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used for MOSI. Defaults to 1 if not present.
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- spi-rx-bus-width - (optional) The bus width (number of data wires) that is
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used for MISO. Defaults to 1 if not present.
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- spi-rx-delay-us - (optional) Microsecond delay after a read transfer.
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- spi-tx-delay-us - (optional) Microsecond delay after a write transfer.
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SPI slave nodes must be children of the SPI controller node.
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In master mode, one or more slave nodes (up to the number of chip selects) can
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be present. Required properties are:
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- compatible - Name of SPI device following generic names recommended
|
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practice.
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- reg - Chip select address of device.
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- spi-max-frequency - Maximum SPI clocking speed of device in Hz.
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|
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In slave mode, the (single) slave node is optional.
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If present, it must be called "slave". Required properties are:
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- compatible - Name of SPI device following generic names recommended
|
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practice.
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|
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All slave nodes can contain the following optional properties:
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- spi-cpol - Empty property indicating device requires inverse clock
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polarity (CPOL) mode.
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- spi-cpha - Empty property indicating device requires shifted clock
|
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phase (CPHA) mode.
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- spi-cs-high - Empty property indicating device requires chip select
|
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active high.
|
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- spi-3wire - Empty property indicating device requires 3-wire mode.
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- spi-lsb-first - Empty property indicating device requires LSB first mode.
|
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- spi-tx-bus-width - The bus width (number of data wires) that is used for MOSI.
|
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Defaults to 1 if not present.
|
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- spi-rx-bus-width - The bus width (number of data wires) that is used for MISO.
|
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Defaults to 1 if not present.
|
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- spi-rx-delay-us - Microsecond delay after a read transfer.
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- spi-tx-delay-us - Microsecond delay after a write transfer.
|
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|
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Some SPI controllers and devices support Dual and Quad SPI transfer mode.
|
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It allows data in the SPI system to be transferred using 2 wires (DUAL) or 4
|
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|
|
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|
|
@ -62,8 +62,8 @@ chips described as using "three wire" signaling: SCK, data, nCSx.
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(That data line is sometimes called MOMI or SISO.)
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Microcontrollers often support both master and slave sides of the SPI
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protocol. This document (and Linux) currently only supports the master
|
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side of SPI interactions.
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protocol. This document (and Linux) supports both the master and slave
|
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sides of SPI interactions.
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Who uses it? On what kinds of systems?
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|
@ -154,9 +154,8 @@ control audio interfaces, present touchscreen sensors as input interfaces,
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or monitor temperature and voltage levels during industrial processing.
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And those might all be sharing the same controller driver.
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|
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A "struct spi_device" encapsulates the master-side interface between
|
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those two types of driver. At this writing, Linux has no slave side
|
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programming interface.
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A "struct spi_device" encapsulates the controller-side interface between
|
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those two types of drivers.
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|
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There is a minimal core of SPI programming interfaces, focussing on
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using the driver model to connect controller and protocol drivers using
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|
@ -177,10 +176,24 @@ shows up in sysfs in several locations:
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/sys/bus/spi/drivers/D ... driver for one or more spi*.* devices
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/sys/class/spi_master/spiB ... symlink (or actual device node) to
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||||
a logical node which could hold class related state for the
|
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controller managing bus "B". All spiB.* devices share one
|
||||
a logical node which could hold class related state for the SPI
|
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master controller managing bus "B". All spiB.* devices share one
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physical SPI bus segment, with SCLK, MOSI, and MISO.
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/sys/devices/.../CTLR/slave ... virtual file for (un)registering the
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slave device for an SPI slave controller.
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Writing the driver name of an SPI slave handler to this file
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registers the slave device; writing "(null)" unregisters the slave
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device.
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Reading from this file shows the name of the slave device ("(null)"
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if not registered).
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/sys/class/spi_slave/spiB ... symlink (or actual device node) to
|
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a logical node which could hold class related state for the SPI
|
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slave controller on bus "B". When registered, a single spiB.*
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device is present here, possible sharing the physical SPI bus
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segment with other SPI slave devices.
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|
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Note that the actual location of the controller's class state depends
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on whether you enabled CONFIG_SYSFS_DEPRECATED or not. At this time,
|
||||
the only class-specific state is the bus number ("B" in "spiB"), so
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||||
|
|
|
|||
|
|
@ -784,6 +784,30 @@ config SPI_TLE62X0
|
|||
|
||||
endif # SPI_MASTER
|
||||
|
||||
# (slave support would go here)
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#
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||||
# SLAVE side ... listening to other SPI masters
|
||||
#
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||||
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||||
config SPI_SLAVE
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bool "SPI slave protocol handlers"
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||||
help
|
||||
If your system has a slave-capable SPI controller, you can enable
|
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slave protocol handlers.
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||||
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if SPI_SLAVE
|
||||
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||||
config SPI_SLAVE_TIME
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||||
tristate "SPI slave handler reporting boot up time"
|
||||
help
|
||||
SPI slave handler responding with the time of reception of the last
|
||||
SPI message.
|
||||
|
||||
config SPI_SLAVE_SYSTEM_CONTROL
|
||||
tristate "SPI slave handler controlling system state"
|
||||
help
|
||||
SPI slave handler to allow remote control of system reboot, power
|
||||
off, halt, and suspend.
|
||||
|
||||
endif # SPI_SLAVE
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|
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endif # SPI
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|
|
|
|||
|
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@ -105,3 +105,7 @@ obj-$(CONFIG_SPI_XILINX) += spi-xilinx.o
|
|||
obj-$(CONFIG_SPI_XLP) += spi-xlp.o
|
||||
obj-$(CONFIG_SPI_XTENSA_XTFPGA) += spi-xtensa-xtfpga.o
|
||||
obj-$(CONFIG_SPI_ZYNQMP_GQSPI) += spi-zynqmp-gqspi.o
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|
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# SPI slave protocol handlers
|
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obj-$(CONFIG_SPI_SLAVE_TIME) += spi-slave-time.o
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obj-$(CONFIG_SPI_SLAVE_SYSTEM_CONTROL) += spi-slave-system-control.o
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|
|
|
|||
|
|
@ -0,0 +1,154 @@
|
|||
/*
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* SPI slave handler controlling system state
|
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*
|
||||
* This SPI slave handler allows remote control of system reboot, power off,
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* halt, and suspend.
|
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*
|
||||
* Copyright (C) 2016-2017 Glider bvba
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*
|
||||
* This file is subject to the terms and conditions of the GNU General Public
|
||||
* License. See the file "COPYING" in the main directory of this archive
|
||||
* for more details.
|
||||
*
|
||||
* Usage (assuming /dev/spidev2.0 corresponds to the SPI master on the remote
|
||||
* system):
|
||||
*
|
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* # reboot='\x7c\x50'
|
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* # poweroff='\x71\x3f'
|
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* # halt='\x38\x76'
|
||||
* # suspend='\x1b\x1b'
|
||||
* # spidev_test -D /dev/spidev2.0 -p $suspend # or $reboot, $poweroff, $halt
|
||||
*/
|
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|
||||
#include <linux/completion.h>
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||||
#include <linux/module.h>
|
||||
#include <linux/reboot.h>
|
||||
#include <linux/suspend.h>
|
||||
#include <linux/spi/spi.h>
|
||||
|
||||
/*
|
||||
* The numbers are chosen to display something human-readable on two 7-segment
|
||||
* displays connected to two 74HC595 shift registers
|
||||
*/
|
||||
#define CMD_REBOOT 0x7c50 /* rb */
|
||||
#define CMD_POWEROFF 0x713f /* OF */
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#define CMD_HALT 0x3876 /* HL */
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#define CMD_SUSPEND 0x1b1b /* ZZ */
|
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|
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struct spi_slave_system_control_priv {
|
||||
struct spi_device *spi;
|
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struct completion finished;
|
||||
struct spi_transfer xfer;
|
||||
struct spi_message msg;
|
||||
__be16 cmd;
|
||||
};
|
||||
|
||||
static
|
||||
int spi_slave_system_control_submit(struct spi_slave_system_control_priv *priv);
|
||||
|
||||
static void spi_slave_system_control_complete(void *arg)
|
||||
{
|
||||
struct spi_slave_system_control_priv *priv = arg;
|
||||
u16 cmd;
|
||||
int ret;
|
||||
|
||||
if (priv->msg.status)
|
||||
goto terminate;
|
||||
|
||||
cmd = be16_to_cpu(priv->cmd);
|
||||
switch (cmd) {
|
||||
case CMD_REBOOT:
|
||||
dev_info(&priv->spi->dev, "Rebooting system...\n");
|
||||
kernel_restart(NULL);
|
||||
|
||||
case CMD_POWEROFF:
|
||||
dev_info(&priv->spi->dev, "Powering off system...\n");
|
||||
kernel_power_off();
|
||||
break;
|
||||
|
||||
case CMD_HALT:
|
||||
dev_info(&priv->spi->dev, "Halting system...\n");
|
||||
kernel_halt();
|
||||
break;
|
||||
|
||||
case CMD_SUSPEND:
|
||||
dev_info(&priv->spi->dev, "Suspending system...\n");
|
||||
pm_suspend(PM_SUSPEND_MEM);
|
||||
break;
|
||||
|
||||
default:
|
||||
dev_warn(&priv->spi->dev, "Unknown command 0x%x\n", cmd);
|
||||
break;
|
||||
}
|
||||
|
||||
ret = spi_slave_system_control_submit(priv);
|
||||
if (ret)
|
||||
goto terminate;
|
||||
|
||||
return;
|
||||
|
||||
terminate:
|
||||
dev_info(&priv->spi->dev, "Terminating\n");
|
||||
complete(&priv->finished);
|
||||
}
|
||||
|
||||
static
|
||||
int spi_slave_system_control_submit(struct spi_slave_system_control_priv *priv)
|
||||
{
|
||||
int ret;
|
||||
|
||||
spi_message_init_with_transfers(&priv->msg, &priv->xfer, 1);
|
||||
|
||||
priv->msg.complete = spi_slave_system_control_complete;
|
||||
priv->msg.context = priv;
|
||||
|
||||
ret = spi_async(priv->spi, &priv->msg);
|
||||
if (ret)
|
||||
dev_err(&priv->spi->dev, "spi_async() failed %d\n", ret);
|
||||
|
||||
return ret;
|
||||
}
|
||||
|
||||
static int spi_slave_system_control_probe(struct spi_device *spi)
|
||||
{
|
||||
struct spi_slave_system_control_priv *priv;
|
||||
int ret;
|
||||
|
||||
priv = devm_kzalloc(&spi->dev, sizeof(*priv), GFP_KERNEL);
|
||||
if (!priv)
|
||||
return -ENOMEM;
|
||||
|
||||
priv->spi = spi;
|
||||
init_completion(&priv->finished);
|
||||
priv->xfer.rx_buf = &priv->cmd;
|
||||
priv->xfer.len = sizeof(priv->cmd);
|
||||
|
||||
ret = spi_slave_system_control_submit(priv);
|
||||
if (ret)
|
||||
return ret;
|
||||
|
||||
spi_set_drvdata(spi, priv);
|
||||
return 0;
|
||||
}
|
||||
|
||||
static int spi_slave_system_control_remove(struct spi_device *spi)
|
||||
{
|
||||
struct spi_slave_system_control_priv *priv = spi_get_drvdata(spi);
|
||||
|
||||
spi_slave_abort(spi);
|
||||
wait_for_completion(&priv->finished);
|
||||
return 0;
|
||||
}
|
||||
|
||||
static struct spi_driver spi_slave_system_control_driver = {
|
||||
.driver = {
|
||||
.name = "spi-slave-system-control",
|
||||
},
|
||||
.probe = spi_slave_system_control_probe,
|
||||
.remove = spi_slave_system_control_remove,
|
||||
};
|
||||
module_spi_driver(spi_slave_system_control_driver);
|
||||
|
||||
MODULE_AUTHOR("Geert Uytterhoeven <geert+renesas@glider.be>");
|
||||
MODULE_DESCRIPTION("SPI slave handler controlling system state");
|
||||
MODULE_LICENSE("GPL v2");
|
||||
|
|
@ -0,0 +1,129 @@
|
|||
/*
|
||||
* SPI slave handler reporting uptime at reception of previous SPI message
|
||||
*
|
||||
* This SPI slave handler sends the time of reception of the last SPI message
|
||||
* as two 32-bit unsigned integers in binary format and in network byte order,
|
||||
* representing the number of seconds and fractional seconds (in microseconds)
|
||||
* since boot up.
|
||||
*
|
||||
* Copyright (C) 2016-2017 Glider bvba
|
||||
*
|
||||
* This file is subject to the terms and conditions of the GNU General Public
|
||||
* License. See the file "COPYING" in the main directory of this archive
|
||||
* for more details.
|
||||
*
|
||||
* Usage (assuming /dev/spidev2.0 corresponds to the SPI master on the remote
|
||||
* system):
|
||||
*
|
||||
* # spidev_test -D /dev/spidev2.0 -p dummy-8B
|
||||
* spi mode: 0x0
|
||||
* bits per word: 8
|
||||
* max speed: 500000 Hz (500 KHz)
|
||||
* RX | 00 00 04 6D 00 09 5B BB ...
|
||||
* ^^^^^ ^^^^^^^^
|
||||
* seconds microseconds
|
||||
*/
|
||||
|
||||
#include <linux/completion.h>
|
||||
#include <linux/module.h>
|
||||
#include <linux/sched/clock.h>
|
||||
#include <linux/spi/spi.h>
|
||||
|
||||
|
||||
struct spi_slave_time_priv {
|
||||
struct spi_device *spi;
|
||||
struct completion finished;
|
||||
struct spi_transfer xfer;
|
||||
struct spi_message msg;
|
||||
__be32 buf[2];
|
||||
};
|
||||
|
||||
static int spi_slave_time_submit(struct spi_slave_time_priv *priv);
|
||||
|
||||
static void spi_slave_time_complete(void *arg)
|
||||
{
|
||||
struct spi_slave_time_priv *priv = arg;
|
||||
int ret;
|
||||
|
||||
ret = priv->msg.status;
|
||||
if (ret)
|
||||
goto terminate;
|
||||
|
||||
ret = spi_slave_time_submit(priv);
|
||||
if (ret)
|
||||
goto terminate;
|
||||
|
||||
return;
|
||||
|
||||
terminate:
|
||||
dev_info(&priv->spi->dev, "Terminating\n");
|
||||
complete(&priv->finished);
|
||||
}
|
||||
|
||||
static int spi_slave_time_submit(struct spi_slave_time_priv *priv)
|
||||
{
|
||||
u32 rem_us;
|
||||
int ret;
|
||||
u64 ts;
|
||||
|
||||
ts = local_clock();
|
||||
rem_us = do_div(ts, 1000000000) / 1000;
|
||||
|
||||
priv->buf[0] = cpu_to_be32(ts);
|
||||
priv->buf[1] = cpu_to_be32(rem_us);
|
||||
|
||||
spi_message_init_with_transfers(&priv->msg, &priv->xfer, 1);
|
||||
|
||||
priv->msg.complete = spi_slave_time_complete;
|
||||
priv->msg.context = priv;
|
||||
|
||||
ret = spi_async(priv->spi, &priv->msg);
|
||||
if (ret)
|
||||
dev_err(&priv->spi->dev, "spi_async() failed %d\n", ret);
|
||||
|
||||
return ret;
|
||||
}
|
||||
|
||||
static int spi_slave_time_probe(struct spi_device *spi)
|
||||
{
|
||||
struct spi_slave_time_priv *priv;
|
||||
int ret;
|
||||
|
||||
priv = devm_kzalloc(&spi->dev, sizeof(*priv), GFP_KERNEL);
|
||||
if (!priv)
|
||||
return -ENOMEM;
|
||||
|
||||
priv->spi = spi;
|
||||
init_completion(&priv->finished);
|
||||
priv->xfer.tx_buf = priv->buf;
|
||||
priv->xfer.len = sizeof(priv->buf);
|
||||
|
||||
ret = spi_slave_time_submit(priv);
|
||||
if (ret)
|
||||
return ret;
|
||||
|
||||
spi_set_drvdata(spi, priv);
|
||||
return 0;
|
||||
}
|
||||
|
||||
static int spi_slave_time_remove(struct spi_device *spi)
|
||||
{
|
||||
struct spi_slave_time_priv *priv = spi_get_drvdata(spi);
|
||||
|
||||
spi_slave_abort(spi);
|
||||
wait_for_completion(&priv->finished);
|
||||
return 0;
|
||||
}
|
||||
|
||||
static struct spi_driver spi_slave_time_driver = {
|
||||
.driver = {
|
||||
.name = "spi-slave-time",
|
||||
},
|
||||
.probe = spi_slave_time_probe,
|
||||
.remove = spi_slave_time_remove,
|
||||
};
|
||||
module_spi_driver(spi_slave_time_driver);
|
||||
|
||||
MODULE_AUTHOR("Geert Uytterhoeven <geert+renesas@glider.be>");
|
||||
MODULE_DESCRIPTION("SPI slave reporting uptime at previous SPI message");
|
||||
MODULE_LICENSE("GPL v2");
|
||||
|
|
@ -1535,15 +1535,6 @@ static int of_spi_parse_dt(struct spi_master *master, struct spi_device *spi,
|
|||
u32 value;
|
||||
int rc;
|
||||
|
||||
/* Device address */
|
||||
rc = of_property_read_u32(nc, "reg", &value);
|
||||
if (rc) {
|
||||
dev_err(&master->dev, "%s has no valid 'reg' property (%d)\n",
|
||||
nc->full_name, rc);
|
||||
return rc;
|
||||
}
|
||||
spi->chip_select = value;
|
||||
|
||||
/* Mode (clock phase/polarity/etc.) */
|
||||
if (of_find_property(nc, "spi-cpha", NULL))
|
||||
spi->mode |= SPI_CPHA;
|
||||
|
|
@ -1593,6 +1584,24 @@ static int of_spi_parse_dt(struct spi_master *master, struct spi_device *spi,
|
|||
}
|
||||
}
|
||||
|
||||
if (spi_controller_is_slave(master)) {
|
||||
if (strcmp(nc->name, "slave")) {
|
||||
dev_err(&master->dev, "%s is not called 'slave'\n",
|
||||
nc->full_name);
|
||||
return -EINVAL;
|
||||
}
|
||||
return 0;
|
||||
}
|
||||
|
||||
/* Device address */
|
||||
rc = of_property_read_u32(nc, "reg", &value);
|
||||
if (rc) {
|
||||
dev_err(&master->dev, "%s has no valid 'reg' property (%d)\n",
|
||||
nc->full_name, rc);
|
||||
return rc;
|
||||
}
|
||||
spi->chip_select = value;
|
||||
|
||||
/* Device speed */
|
||||
rc = of_property_read_u32(nc, "spi-max-frequency", &value);
|
||||
if (rc) {
|
||||
|
|
@ -1658,8 +1667,8 @@ err_out:
|
|||
* of_register_spi_devices() - Register child devices onto the SPI bus
|
||||
* @master: Pointer to spi_master device
|
||||
*
|
||||
* Registers an spi_device for each child node of master node which has a 'reg'
|
||||
* property.
|
||||
* Registers an spi_device for each child node of controller node which
|
||||
* represents a valid SPI slave.
|
||||
*/
|
||||
static void of_register_spi_devices(struct spi_master *master)
|
||||
{
|
||||
|
|
@ -1828,28 +1837,129 @@ static struct class spi_master_class = {
|
|||
.dev_groups = spi_master_groups,
|
||||
};
|
||||
|
||||
#ifdef CONFIG_SPI_SLAVE
|
||||
/**
|
||||
* spi_slave_abort - abort the ongoing transfer request on an SPI slave
|
||||
* controller
|
||||
* @spi: device used for the current transfer
|
||||
*/
|
||||
int spi_slave_abort(struct spi_device *spi)
|
||||
{
|
||||
struct spi_master *master = spi->master;
|
||||
|
||||
if (spi_controller_is_slave(master) && master->slave_abort)
|
||||
return master->slave_abort(master);
|
||||
|
||||
return -ENOTSUPP;
|
||||
}
|
||||
EXPORT_SYMBOL_GPL(spi_slave_abort);
|
||||
|
||||
static int match_true(struct device *dev, void *data)
|
||||
{
|
||||
return 1;
|
||||
}
|
||||
|
||||
static ssize_t spi_slave_show(struct device *dev,
|
||||
struct device_attribute *attr, char *buf)
|
||||
{
|
||||
struct spi_master *ctlr = container_of(dev, struct spi_master, dev);
|
||||
struct device *child;
|
||||
|
||||
child = device_find_child(&ctlr->dev, NULL, match_true);
|
||||
return sprintf(buf, "%s\n",
|
||||
child ? to_spi_device(child)->modalias : NULL);
|
||||
}
|
||||
|
||||
static ssize_t spi_slave_store(struct device *dev,
|
||||
struct device_attribute *attr, const char *buf,
|
||||
size_t count)
|
||||
{
|
||||
struct spi_master *ctlr = container_of(dev, struct spi_master, dev);
|
||||
struct spi_device *spi;
|
||||
struct device *child;
|
||||
char name[32];
|
||||
int rc;
|
||||
|
||||
rc = sscanf(buf, "%31s", name);
|
||||
if (rc != 1 || !name[0])
|
||||
return -EINVAL;
|
||||
|
||||
child = device_find_child(&ctlr->dev, NULL, match_true);
|
||||
if (child) {
|
||||
/* Remove registered slave */
|
||||
device_unregister(child);
|
||||
put_device(child);
|
||||
}
|
||||
|
||||
if (strcmp(name, "(null)")) {
|
||||
/* Register new slave */
|
||||
spi = spi_alloc_device(ctlr);
|
||||
if (!spi)
|
||||
return -ENOMEM;
|
||||
|
||||
strlcpy(spi->modalias, name, sizeof(spi->modalias));
|
||||
|
||||
rc = spi_add_device(spi);
|
||||
if (rc) {
|
||||
spi_dev_put(spi);
|
||||
return rc;
|
||||
}
|
||||
}
|
||||
|
||||
return count;
|
||||
}
|
||||
|
||||
static DEVICE_ATTR(slave, 0644, spi_slave_show, spi_slave_store);
|
||||
|
||||
static struct attribute *spi_slave_attrs[] = {
|
||||
&dev_attr_slave.attr,
|
||||
NULL,
|
||||
};
|
||||
|
||||
static const struct attribute_group spi_slave_group = {
|
||||
.attrs = spi_slave_attrs,
|
||||
};
|
||||
|
||||
static const struct attribute_group *spi_slave_groups[] = {
|
||||
&spi_master_statistics_group,
|
||||
&spi_slave_group,
|
||||
NULL,
|
||||
};
|
||||
|
||||
static struct class spi_slave_class = {
|
||||
.name = "spi_slave",
|
||||
.owner = THIS_MODULE,
|
||||
.dev_release = spi_master_release,
|
||||
.dev_groups = spi_slave_groups,
|
||||
};
|
||||
#else
|
||||
extern struct class spi_slave_class; /* dummy */
|
||||
#endif
|
||||
|
||||
/**
|
||||
* spi_alloc_master - allocate SPI master controller
|
||||
* __spi_alloc_controller - allocate an SPI master or slave controller
|
||||
* @dev: the controller, possibly using the platform_bus
|
||||
* @size: how much zeroed driver-private data to allocate; the pointer to this
|
||||
* memory is in the driver_data field of the returned device,
|
||||
* accessible with spi_master_get_devdata().
|
||||
* @slave: flag indicating whether to allocate an SPI master (false) or SPI
|
||||
* slave (true) controller
|
||||
* Context: can sleep
|
||||
*
|
||||
* This call is used only by SPI master controller drivers, which are the
|
||||
* This call is used only by SPI controller drivers, which are the
|
||||
* only ones directly touching chip registers. It's how they allocate
|
||||
* an spi_master structure, prior to calling spi_register_master().
|
||||
*
|
||||
* This must be called from context that can sleep.
|
||||
*
|
||||
* The caller is responsible for assigning the bus number and initializing
|
||||
* the master's methods before calling spi_register_master(); and (after errors
|
||||
* The caller is responsible for assigning the bus number and initializing the
|
||||
* controller's methods before calling spi_register_master(); and (after errors
|
||||
* adding the device) calling spi_master_put() to prevent a memory leak.
|
||||
*
|
||||
* Return: the SPI master structure on success, else NULL.
|
||||
* Return: the SPI controller structure on success, else NULL.
|
||||
*/
|
||||
struct spi_master *spi_alloc_master(struct device *dev, unsigned size)
|
||||
struct spi_master *__spi_alloc_controller(struct device *dev,
|
||||
unsigned int size, bool slave)
|
||||
{
|
||||
struct spi_master *master;
|
||||
|
||||
|
|
@ -1863,14 +1973,18 @@ struct spi_master *spi_alloc_master(struct device *dev, unsigned size)
|
|||
device_initialize(&master->dev);
|
||||
master->bus_num = -1;
|
||||
master->num_chipselect = 1;
|
||||
master->dev.class = &spi_master_class;
|
||||
master->slave = slave;
|
||||
if (IS_ENABLED(CONFIG_SPI_SLAVE) && slave)
|
||||
master->dev.class = &spi_slave_class;
|
||||
else
|
||||
master->dev.class = &spi_master_class;
|
||||
master->dev.parent = dev;
|
||||
pm_suspend_ignore_children(&master->dev, true);
|
||||
spi_master_set_devdata(master, &master[1]);
|
||||
|
||||
return master;
|
||||
}
|
||||
EXPORT_SYMBOL_GPL(spi_alloc_master);
|
||||
EXPORT_SYMBOL_GPL(__spi_alloc_controller);
|
||||
|
||||
#ifdef CONFIG_OF
|
||||
static int of_spi_register_master(struct spi_master *master)
|
||||
|
|
@ -1946,9 +2060,11 @@ int spi_register_master(struct spi_master *master)
|
|||
if (!dev)
|
||||
return -ENODEV;
|
||||
|
||||
status = of_spi_register_master(master);
|
||||
if (status)
|
||||
return status;
|
||||
if (!spi_controller_is_slave(master)) {
|
||||
status = of_spi_register_master(master);
|
||||
if (status)
|
||||
return status;
|
||||
}
|
||||
|
||||
/* even if it's just one always-selected device, there must
|
||||
* be at least one chipselect
|
||||
|
|
@ -1985,8 +2101,9 @@ int spi_register_master(struct spi_master *master)
|
|||
status = device_add(&master->dev);
|
||||
if (status < 0)
|
||||
goto done;
|
||||
dev_dbg(dev, "registered master %s%s\n", dev_name(&master->dev),
|
||||
dynamic ? " (dynamic)" : "");
|
||||
dev_dbg(dev, "registered %s %s%s\n",
|
||||
spi_controller_is_slave(master) ? "slave" : "master",
|
||||
dev_name(&master->dev), dynamic ? " (dynamic)" : "");
|
||||
|
||||
/* If we're using a queued driver, start the queue */
|
||||
if (master->transfer)
|
||||
|
|
@ -2021,7 +2138,7 @@ static void devm_spi_unregister(struct device *dev, void *res)
|
|||
}
|
||||
|
||||
/**
|
||||
* dev_spi_register_master - register managed SPI master controller
|
||||
* devm_spi_register_master - register managed SPI master controller
|
||||
* @dev: device managing SPI master
|
||||
* @master: initialized master, originally from spi_alloc_master()
|
||||
* Context: can sleep
|
||||
|
|
@ -3159,6 +3276,9 @@ static struct spi_master *of_find_spi_master_by_node(struct device_node *node)
|
|||
|
||||
dev = class_find_device(&spi_master_class, NULL, node,
|
||||
__spi_of_master_match);
|
||||
if (!dev && IS_ENABLED(CONFIG_SPI_SLAVE))
|
||||
dev = class_find_device(&spi_slave_class, NULL, node,
|
||||
__spi_of_master_match);
|
||||
if (!dev)
|
||||
return NULL;
|
||||
|
||||
|
|
@ -3240,6 +3360,9 @@ static struct spi_master *acpi_spi_find_master_by_adev(struct acpi_device *adev)
|
|||
|
||||
dev = class_find_device(&spi_master_class, NULL, adev,
|
||||
spi_acpi_master_match);
|
||||
if (!dev && IS_ENABLED(CONFIG_SPI_SLAVE))
|
||||
dev = class_find_device(&spi_slave_class, NULL, adev,
|
||||
spi_acpi_master_match);
|
||||
if (!dev)
|
||||
return NULL;
|
||||
|
||||
|
|
@ -3312,6 +3435,12 @@ static int __init spi_init(void)
|
|||
if (status < 0)
|
||||
goto err2;
|
||||
|
||||
if (IS_ENABLED(CONFIG_SPI_SLAVE)) {
|
||||
status = class_register(&spi_slave_class);
|
||||
if (status < 0)
|
||||
goto err3;
|
||||
}
|
||||
|
||||
if (IS_ENABLED(CONFIG_OF_DYNAMIC))
|
||||
WARN_ON(of_reconfig_notifier_register(&spi_of_notifier));
|
||||
if (IS_ENABLED(CONFIG_ACPI))
|
||||
|
|
@ -3319,6 +3448,8 @@ static int __init spi_init(void)
|
|||
|
||||
return 0;
|
||||
|
||||
err3:
|
||||
class_unregister(&spi_master_class);
|
||||
err2:
|
||||
bus_unregister(&spi_bus_type);
|
||||
err1:
|
||||
|
|
|
|||
|
|
@ -29,8 +29,8 @@ struct spi_transfer;
|
|||
struct spi_flash_read_message;
|
||||
|
||||
/*
|
||||
* INTERFACES between SPI master-side drivers and SPI infrastructure.
|
||||
* (There's no SPI slave support for Linux yet...)
|
||||
* INTERFACES between SPI master-side drivers and SPI slave protocol handlers,
|
||||
* and SPI infrastructure.
|
||||
*/
|
||||
extern struct bus_type spi_bus_type;
|
||||
|
||||
|
|
@ -311,6 +311,7 @@ static inline void spi_unregister_driver(struct spi_driver *sdrv)
|
|||
* @min_speed_hz: Lowest supported transfer speed
|
||||
* @max_speed_hz: Highest supported transfer speed
|
||||
* @flags: other constraints relevant to this driver
|
||||
* @slave: indicates that this is an SPI slave controller
|
||||
* @max_transfer_size: function that returns the max transfer size for
|
||||
* a &spi_device; may be %NULL, so the default %SIZE_MAX will be used.
|
||||
* @max_message_size: function that returns the max message size for
|
||||
|
|
@ -374,6 +375,7 @@ static inline void spi_unregister_driver(struct spi_driver *sdrv)
|
|||
* @handle_err: the subsystem calls the driver to handle an error that occurs
|
||||
* in the generic implementation of transfer_one_message().
|
||||
* @unprepare_message: undo any work done by prepare_message().
|
||||
* @slave_abort: abort the ongoing transfer request on an SPI slave controller
|
||||
* @spi_flash_read: to support spi-controller hardwares that provide
|
||||
* accelerated interface to read from flash devices.
|
||||
* @spi_flash_can_dma: analogous to can_dma() interface, but for
|
||||
|
|
@ -447,6 +449,9 @@ struct spi_master {
|
|||
#define SPI_MASTER_MUST_TX BIT(4) /* requires tx */
|
||||
#define SPI_MASTER_GPIO_SS BIT(5) /* GPIO CS must select slave */
|
||||
|
||||
/* flag indicating this is an SPI slave controller */
|
||||
bool slave;
|
||||
|
||||
/*
|
||||
* on some hardware transfer / message size may be constrained
|
||||
* the limit may depend on device transfer settings
|
||||
|
|
@ -539,6 +544,7 @@ struct spi_master {
|
|||
struct spi_message *message);
|
||||
int (*unprepare_message)(struct spi_master *master,
|
||||
struct spi_message *message);
|
||||
int (*slave_abort)(struct spi_master *spi);
|
||||
int (*spi_flash_read)(struct spi_device *spi,
|
||||
struct spi_flash_read_message *msg);
|
||||
bool (*spi_flash_can_dma)(struct spi_device *spi,
|
||||
|
|
@ -595,6 +601,11 @@ static inline void spi_master_put(struct spi_master *master)
|
|||
put_device(&master->dev);
|
||||
}
|
||||
|
||||
static inline bool spi_controller_is_slave(struct spi_master *ctlr)
|
||||
{
|
||||
return IS_ENABLED(CONFIG_SPI_SLAVE) && ctlr->slave;
|
||||
}
|
||||
|
||||
/* PM calls that need to be issued by the driver */
|
||||
extern int spi_master_suspend(struct spi_master *master);
|
||||
extern int spi_master_resume(struct spi_master *master);
|
||||
|
|
@ -605,8 +616,23 @@ extern void spi_finalize_current_message(struct spi_master *master);
|
|||
extern void spi_finalize_current_transfer(struct spi_master *master);
|
||||
|
||||
/* the spi driver core manages memory for the spi_master classdev */
|
||||
extern struct spi_master *
|
||||
spi_alloc_master(struct device *host, unsigned size);
|
||||
extern struct spi_master *__spi_alloc_controller(struct device *host,
|
||||
unsigned int size, bool slave);
|
||||
|
||||
static inline struct spi_master *spi_alloc_master(struct device *host,
|
||||
unsigned int size)
|
||||
{
|
||||
return __spi_alloc_controller(host, size, false);
|
||||
}
|
||||
|
||||
static inline struct spi_master *spi_alloc_slave(struct device *host,
|
||||
unsigned int size)
|
||||
{
|
||||
if (!IS_ENABLED(CONFIG_SPI_SLAVE))
|
||||
return NULL;
|
||||
|
||||
return __spi_alloc_controller(host, size, true);
|
||||
}
|
||||
|
||||
extern int spi_register_master(struct spi_master *master);
|
||||
extern int devm_spi_register_master(struct device *dev,
|
||||
|
|
@ -912,6 +938,7 @@ extern int spi_setup(struct spi_device *spi);
|
|||
extern int spi_async(struct spi_device *spi, struct spi_message *message);
|
||||
extern int spi_async_locked(struct spi_device *spi,
|
||||
struct spi_message *message);
|
||||
extern int spi_slave_abort(struct spi_device *spi);
|
||||
|
||||
static inline size_t
|
||||
spi_max_message_size(struct spi_device *spi)
|
||||
|
|
|
|||
Loading…
Reference in New Issue