diff options
41 files changed, 4944 insertions, 2483 deletions
diff --git a/Documentation/devicetree/bindings/i2c/i2c-aspeed.txt b/Documentation/devicetree/bindings/i2c/i2c-aspeed.txt new file mode 100644 index 000000000000..bd6480b19535 --- /dev/null +++ b/Documentation/devicetree/bindings/i2c/i2c-aspeed.txt @@ -0,0 +1,48 @@ +Device tree configuration for the I2C busses on the AST24XX and AST25XX SoCs. + +Required Properties: +- #address-cells : should be 1 +- #size-cells : should be 0 +- reg : address offset and range of bus +- compatible : should be "aspeed,ast2400-i2c-bus" + or "aspeed,ast2500-i2c-bus" +- clocks : root clock of bus, should reference the APB + clock +- interrupts : interrupt number +- interrupt-parent : interrupt controller for bus, should reference a + aspeed,ast2400-i2c-ic or aspeed,ast2500-i2c-ic + interrupt controller + +Optional Properties: +- bus-frequency : frequency of the bus clock in Hz defaults to 100 kHz when not + specified +- multi-master : states that there is another master active on this bus. + +Example: + +i2c { + compatible = "simple-bus"; + #address-cells = <1>; + #size-cells = <1>; + ranges = <0 0x1e78a000 0x1000>; + + i2c_ic: interrupt-controller@0 { + #interrupt-cells = <1>; + compatible = "aspeed,ast2400-i2c-ic"; + reg = <0x0 0x40>; + interrupts = <12>; + interrupt-controller; + }; + + i2c0: i2c-bus@40 { + #address-cells = <1>; + #size-cells = <0>; + #interrupt-cells = <1>; + reg = <0x40 0x40>; + compatible = "aspeed,ast2400-i2c-bus"; + clocks = <&clk_apb>; + bus-frequency = <100000>; + interrupts = <0>; + interrupt-parent = <&i2c_ic>; + }; +}; diff --git a/Documentation/devicetree/bindings/i2c/i2c-designware.txt b/Documentation/devicetree/bindings/i2c/i2c-designware.txt index fee26dc3e858..fbb0a6d8b964 100644 --- a/Documentation/devicetree/bindings/i2c/i2c-designware.txt +++ b/Documentation/devicetree/bindings/i2c/i2c-designware.txt @@ -20,7 +20,7 @@ Optional properties : - i2c-sda-falling-time-ns : should contain the SDA falling time in nanoseconds. This value which is by default 300ns is used to compute the tHIGH period. -Example : +Examples : i2c@f0000 { #address-cells = <1>; @@ -43,3 +43,17 @@ Example : i2c-sda-falling-time-ns = <300>; i2c-scl-falling-time-ns = <300>; }; + + i2c@1120000 { + #address-cells = <1>; + #size-cells = <0>; + reg = <0x2000 0x100>; + clock-frequency = <400000>; + clocks = <&i2cclk>; + interrupts = <0>; + + eeprom@64 { + compatible = "linux,slave-24c02"; + reg = <0x40000064>; + }; + }; diff --git a/Documentation/devicetree/bindings/i2c/i2c-pca-platform.txt b/Documentation/devicetree/bindings/i2c/i2c-pca-platform.txt new file mode 100644 index 000000000000..f1f3876bb8e8 --- /dev/null +++ b/Documentation/devicetree/bindings/i2c/i2c-pca-platform.txt @@ -0,0 +1,29 @@ +* NXP PCA PCA9564/PCA9665 I2C controller + +The PCA9564/PCA9665 serves as an interface between most standard +parallel-bus microcontrollers/microprocessors and the serial I2C-bus +and allows the parallel bus system to communicate bi-directionally +with the I2C-bus. + +Required properties : + + - reg : Offset and length of the register set for the device + - compatible : one of "nxp,pca9564" or "nxp,pca9665" + +Optional properties + - interrupts : the interrupt number + - interrupt-parent : the phandle for the interrupt controller. + If an interrupt is not specified polling will be used. + - reset-gpios : gpio specifier for gpio connected to RESET_N pin. As the line + is active low, it should be marked GPIO_ACTIVE_LOW. + - clock-frequency : I2C bus frequency. + +Example: + i2c0: i2c@80000 { + compatible = "nxp,pca9564"; + #address-cells = <1>; + #size-cells = <0>; + reg = <0x80000 0x4>; + reset-gpios = <&gpio1 0 GPIO_ACTIVE_LOW>; + clock-frequency = <100000>; + }; diff --git a/Documentation/devicetree/bindings/i2c/i2c-zx2967.txt b/Documentation/devicetree/bindings/i2c/i2c-zx2967.txt new file mode 100644 index 000000000000..cb806d1ae4c9 --- /dev/null +++ b/Documentation/devicetree/bindings/i2c/i2c-zx2967.txt @@ -0,0 +1,22 @@ +ZTE zx2967 I2C controller + +Required properties: + - compatible: must be "zte,zx296718-i2c" + - reg: physical address and length of the device registers + - interrupts: a single interrupt specifier + - clocks: clock for the device + - #address-cells: should be <1> + - #size-cells: should be <0> + - clock-frequency: the desired I2C bus clock frequency. + +Examples: + + i2c@112000 { + compatible = "zte,zx296718-i2c"; + reg = <0x00112000 0x1000>; + interrupts = <GIC_SPI 112 IRQ_TYPE_LEVEL_HIGH>; + clocks = <&osc24m>; + #address-cells = <1> + #size-cells = <0>; + clock-frequency = <1600000>; + }; diff --git a/Documentation/driver-api/i2c.rst b/Documentation/driver-api/i2c.rst index 0bf86a445d01..7582c079d747 100644 --- a/Documentation/driver-api/i2c.rst +++ b/Documentation/driver-api/i2c.rst @@ -41,5 +41,8 @@ i2c_adapter devices which don't support those I2C operations. .. kernel-doc:: drivers/i2c/i2c-boardinfo.c :functions: i2c_register_board_info -.. kernel-doc:: drivers/i2c/i2c-core.c +.. kernel-doc:: drivers/i2c/i2c-core-base.c + :export: + +.. kernel-doc:: drivers/i2c/i2c-core-smbus.c :export: diff --git a/Documentation/i2c/busses/i2c-i801 b/Documentation/i2c/busses/i2c-i801 index 820d9040de16..0500193434cb 100644 --- a/Documentation/i2c/busses/i2c-i801 +++ b/Documentation/i2c/busses/i2c-i801 @@ -34,6 +34,8 @@ Supported adapters: * Intel Broxton (SOC) * Intel Lewisburg (PCH) * Intel Gemini Lake (SOC) + * Intel Cannon Lake-H (PCH) + * Intel Cannon Lake-LP (PCH) Datasheets: Publicly available at the Intel website On Intel Patsburg and later chipsets, both the normal host SMBus controller diff --git a/Documentation/i2c/dev-interface b/Documentation/i2c/dev-interface index bcf919d8625c..5ff19447ac44 100644 --- a/Documentation/i2c/dev-interface +++ b/Documentation/i2c/dev-interface @@ -191,7 +191,7 @@ checking on future transactions.) 4* Other ioctl() calls are converted to in-kernel function calls by i2c-dev. Examples include I2C_FUNCS, which queries the I2C adapter functionality using i2c.h:i2c_get_functionality(), and I2C_SMBUS, which -performs an SMBus transaction using i2c-core.c:i2c_smbus_xfer(). +performs an SMBus transaction using i2c-core-smbus.c:i2c_smbus_xfer(). The i2c-dev driver is responsible for checking all the parameters that come from user-space for validity. After this point, there is no @@ -200,13 +200,13 @@ and calls that would have been performed by kernel I2C chip drivers directly. This means that I2C bus drivers don't need to implement anything special to support access from user-space. -5* These i2c-core.c/i2c.h functions are wrappers to the actual -implementation of your I2C bus driver. Each adapter must declare -callback functions implementing these standard calls. -i2c.h:i2c_get_functionality() calls i2c_adapter.algo->functionality(), -while i2c-core.c:i2c_smbus_xfer() calls either +5* These i2c.h functions are wrappers to the actual implementation of +your I2C bus driver. Each adapter must declare callback functions +implementing these standard calls. i2c.h:i2c_get_functionality() calls +i2c_adapter.algo->functionality(), while +i2c-core-smbus.c:i2c_smbus_xfer() calls either adapter.algo->smbus_xfer() if it is implemented, or if not, -i2c-core.c:i2c_smbus_xfer_emulated() which in turn calls +i2c-core-smbus.c:i2c_smbus_xfer_emulated() which in turn calls i2c_adapter.algo->master_xfer(). After your I2C bus driver has processed these requests, execution runs diff --git a/MAINTAINERS b/MAINTAINERS index f6ec1be48609..1347726cf9d5 100644 --- a/MAINTAINERS +++ b/MAINTAINERS @@ -1139,6 +1139,18 @@ F: arch/arm/mach-aspeed/ F: arch/arm/boot/dts/aspeed-* F: drivers/*/*aspeed* +ARM/ASPEED I2C DRIVER +M: Brendan Higgins <brendanhiggins@google.com> +R: Benjamin Herrenschmidt <benh@kernel.crashing.org> +R: Joel Stanley <joel@jms.id.au> +L: linux-i2c@vger.kernel.org +L: openbmc@lists.ozlabs.org +S: Maintained +F: drivers/irqchip/irq-aspeed-i2c-ic.c +F: drivers/i2c/busses/i2c-aspeed.c +F: Documentation/devicetree/bindings/interrupt-controller/aspeed,ast2400-i2c-ic.txt +F: Documentation/devicetree/bindings/i2c/i2c-aspeed.txt + ARM/ATMEL AT91RM9200, AT91SAM9 AND SAMA5 SOC SUPPORT M: Nicolas Ferre <nicolas.ferre@microchip.com> M: Alexandre Belloni <alexandre.belloni@free-electrons.com> @@ -6382,6 +6394,7 @@ M: Mika Westerberg <mika.westerberg@linux.intel.com> L: linux-i2c@vger.kernel.org L: linux-acpi@vger.kernel.org S: Maintained +F: drivers/i2c/i2c-core-acpi.c I2C-TAOS-EVM DRIVER M: Jean Delvare <jdelvare@suse.com> diff --git a/drivers/i2c/Makefile b/drivers/i2c/Makefile index 45095b3d16a9..7bb65a4369e1 100644 --- a/drivers/i2c/Makefile +++ b/drivers/i2c/Makefile @@ -4,6 +4,11 @@ obj-$(CONFIG_I2C_BOARDINFO) += i2c-boardinfo.o obj-$(CONFIG_I2C) += i2c-core.o +i2c-core-objs := i2c-core-base.o i2c-core-smbus.o +i2c-core-$(CONFIG_ACPI) += i2c-core-acpi.o +i2c-core-$(CONFIG_I2C_SLAVE) += i2c-core-slave.o +i2c-core-$(CONFIG_OF) += i2c-core-of.o + obj-$(CONFIG_I2C_SMBUS) += i2c-smbus.o obj-$(CONFIG_I2C_CHARDEV) += i2c-dev.o obj-$(CONFIG_I2C_MUX) += i2c-mux.o @@ -12,4 +17,4 @@ obj-$(CONFIG_I2C_STUB) += i2c-stub.o obj-$(CONFIG_I2C_SLAVE_EEPROM) += i2c-slave-eeprom.o ccflags-$(CONFIG_I2C_DEBUG_CORE) := -DDEBUG -CFLAGS_i2c-core.o := -Wno-deprecated-declarations +CFLAGS_i2c-core-base.o := -Wno-deprecated-declarations diff --git a/drivers/i2c/algos/i2c-algo-bit.c b/drivers/i2c/algos/i2c-algo-bit.c index a8e89df665b9..1147bddb8b2c 100644 --- a/drivers/i2c/algos/i2c-algo-bit.c +++ b/drivers/i2c/algos/i2c-algo-bit.c @@ -553,9 +553,16 @@ static int bit_xfer(struct i2c_adapter *i2c_adap, nak_ok = pmsg->flags & I2C_M_IGNORE_NAK; if (!(pmsg->flags & I2C_M_NOSTART)) { if (i) { - bit_dbg(3, &i2c_adap->dev, "emitting " - "repeated start condition\n"); - i2c_repstart(adap); + if (msgs[i - 1].flags & I2C_M_STOP) { + bit_dbg(3, &i2c_adap->dev, + "emitting enforced stop/start condition\n"); + i2c_stop(adap); + i2c_start(adap); + } else { + bit_dbg(3, &i2c_adap->dev, + "emitting repeated start condition\n"); + i2c_repstart(adap); + } } ret = bit_doAddress(i2c_adap, pmsg); if ((ret != 0) && !nak_ok) { diff --git a/drivers/i2c/busses/Kconfig b/drivers/i2c/busses/Kconfig index 144cbadc7c72..1006b230b236 100644 --- a/drivers/i2c/busses/Kconfig +++ b/drivers/i2c/busses/Kconfig @@ -129,6 +129,8 @@ config I2C_I801 Broxton (SOC) Lewisburg (PCH) Gemini Lake (SOC) + Cannon Lake-H (PCH) + Cannon Lake-LP (PCH) This driver can also be built as a module. If so, the module will be called i2c-i801. @@ -326,6 +328,16 @@ config I2C_POWERMAC comment "I2C system bus drivers (mostly embedded / system-on-chip)" +config I2C_ASPEED + tristate "Aspeed I2C Controller" + depends on ARCH_ASPEED || COMPILE_TEST + help + If you say yes to this option, support will be included for the + Aspeed I2C controller. + + This driver can also be built as a module. If so, the module + will be called i2c-aspeed. + config I2C_AT91 tristate "Atmel AT91 I2C Two-Wire interface (TWI)" depends on ARCH_AT91 @@ -474,11 +486,22 @@ config I2C_DESIGNWARE_PLATFORM depends on (ACPI && COMMON_CLK) || !ACPI help If you say yes to this option, support will be included for the - Synopsys DesignWare I2C adapter. Only master mode is supported. + Synopsys DesignWare I2C adapter. This driver can also be built as a module. If so, the module will be called i2c-designware-platform. +config I2C_DESIGNWARE_SLAVE + bool "Synopsys DesignWare Slave" + select I2C_SLAVE + depends on I2C_DESIGNWARE_PLATFORM + help + If you say yes to this option, support will be included for the + Synopsys DesignWare I2C slave adapter. + + This is not a standalone module, this module compiles together with + i2c-designware-core. + config I2C_DESIGNWARE_PCI tristate "Synopsys DesignWare PCI" depends on PCI @@ -1258,4 +1281,13 @@ config I2C_OPAL This driver can also be built as a module. If so, the module will be called as i2c-opal. +config I2C_ZX2967 + tristate "ZTE ZX2967 I2C support" + depends on ARCH_ZX + default y + help + Selecting this option will add ZX2967 I2C driver. + This driver can also be built as a module. If so, the module will be + called i2c-zx2967. + endmenu diff --git a/drivers/i2c/busses/Makefile b/drivers/i2c/busses/Makefile index 30b60855fbcd..1b2fc815a4d8 100644 --- a/drivers/i2c/busses/Makefile +++ b/drivers/i2c/busses/Makefile @@ -29,6 +29,7 @@ obj-$(CONFIG_I2C_HYDRA) += i2c-hydra.o obj-$(CONFIG_I2C_POWERMAC) += i2c-powermac.o # Embedded system I2C/SMBus host controller drivers +obj-$(CONFIG_I2C_ASPEED) += i2c-aspeed.o obj-$(CONFIG_I2C_AT91) += i2c-at91.o obj-$(CONFIG_I2C_AU1550) += i2c-au1550.o obj-$(CONFIG_I2C_AXXIA) += i2c-axxia.o @@ -40,6 +41,10 @@ obj-$(CONFIG_I2C_CBUS_GPIO) += i2c-cbus-gpio.o obj-$(CONFIG_I2C_CPM) += i2c-cpm.o obj-$(CONFIG_I2C_DAVINCI) += i2c-davinci.o obj-$(CONFIG_I2C_DESIGNWARE_CORE) += i2c-designware-core.o +i2c-designware-core-objs := i2c-designware-common.o i2c-designware-master.o +ifeq ($(CONFIG_I2C_DESIGNWARE_SLAVE),y) +i2c-designware-core-objs += i2c-designware-slave.o +endif obj-$(CONFIG_I2C_DESIGNWARE_PLATFORM) += i2c-designware-platform.o i2c-designware-platform-objs := i2c-designware-platdrv.o i2c-designware-platform-$(CONFIG_I2C_DESIGNWARE_BAYTRAIL) += i2c-designware-baytrail.o @@ -102,6 +107,7 @@ obj-$(CONFIG_I2C_XILINX) += i2c-xiic.o obj-$(CONFIG_I2C_XLR) += i2c-xlr.o obj-$(CONFIG_I2C_XLP9XX) += i2c-xlp9xx.o obj-$(CONFIG_I2C_RCAR) += i2c-rcar.o +obj-$(CONFIG_I2C_ZX2967) += i2c-zx2967.o # External I2C/SMBus adapter drivers obj-$(CONFIG_I2C_DIOLAN_U2C) += i2c-diolan-u2c.o diff --git a/drivers/i2c/busses/i2c-aspeed.c b/drivers/i2c/busses/i2c-aspeed.c new file mode 100644 index 000000000000..f19348328a71 --- /dev/null +++ b/drivers/i2c/busses/i2c-aspeed.c @@ -0,0 +1,891 @@ +/* + * Aspeed 24XX/25XX I2C Controller. + * + * Copyright (C) 2012-2017 ASPEED Technology Inc. + * Copyright 2017 IBM Corporation + * Copyright 2017 Google, Inc. + * + * This program is free software; you can redistribute it and/or modify + * it under the terms of the GNU General Public License version 2 as + * published by the Free Software Foundation. + */ + +#include <linux/clk.h> +#include <linux/completion.h> +#include <linux/err.h> +#include <linux/errno.h> +#include <linux/i2c.h> +#include <linux/init.h> +#include <linux/interrupt.h> +#include <linux/io.h> +#include <linux/irq.h> +#include <linux/irqchip/chained_irq.h> +#include <linux/irqdomain.h> +#include <linux/kernel.h> +#include <linux/module.h> +#include <linux/of_address.h> +#include <linux/of_irq.h> +#include <linux/of_platform.h> +#include <linux/platform_device.h> +#include <linux/slab.h> + +/* I2C Register */ +#define ASPEED_I2C_FUN_CTRL_REG 0x00 +#define ASPEED_I2C_AC_TIMING_REG1 0x04 +#define ASPEED_I2C_AC_TIMING_REG2 0x08 +#define ASPEED_I2C_INTR_CTRL_REG 0x0c +#define ASPEED_I2C_INTR_STS_REG 0x10 +#define ASPEED_I2C_CMD_REG 0x14 +#define ASPEED_I2C_DEV_ADDR_REG 0x18 +#define ASPEED_I2C_BYTE_BUF_REG 0x20 + +/* Global Register Definition */ +/* 0x00 : I2C Interrupt Status Register */ +/* 0x08 : I2C Interrupt Target Assignment */ + +/* Device Register Definition */ +/* 0x00 : I2CD Function Control Register */ +#define ASPEED_I2CD_MULTI_MASTER_DIS BIT(15) +#define ASPEED_I2CD_SDA_DRIVE_1T_EN BIT(8) +#define ASPEED_I2CD_M_SDA_DRIVE_1T_EN BIT(7) +#define ASPEED_I2CD_M_HIGH_SPEED_EN BIT(6) +#define ASPEED_I2CD_SLAVE_EN BIT(1) +#define ASPEED_I2CD_MASTER_EN BIT(0) + +/* 0x04 : I2CD Clock and AC Timing Control Register #1 */ +#define ASPEED_I2CD_TIME_SCL_HIGH_SHIFT 16 +#define ASPEED_I2CD_TIME_SCL_HIGH_MASK GENMASK(19, 16) +#define ASPEED_I2CD_TIME_SCL_LOW_SHIFT 12 +#define ASPEED_I2CD_TIME_SCL_LOW_MASK GENMASK(15, 12) +#define ASPEED_I2CD_TIME_BASE_DIVISOR_MASK GENMASK(3, 0) +#define ASPEED_I2CD_TIME_SCL_REG_MAX GENMASK(3, 0) +/* 0x08 : I2CD Clock and AC Timing Control Register #2 */ +#define ASPEED_NO_TIMEOUT_CTRL 0 + +/* 0x0c : I2CD Interrupt Control Register & + * 0x10 : I2CD Interrupt Status Register + * + * These share bit definitions, so use the same values for the enable & + * status bits. + */ +#define ASPEED_I2CD_INTR_SDA_DL_TIMEOUT BIT(14) +#define ASPEED_I2CD_INTR_BUS_RECOVER_DONE BIT(13) +#define ASPEED_I2CD_INTR_SLAVE_MATCH BIT(7) +#define ASPEED_I2CD_INTR_SCL_TIMEOUT BIT(6) +#define ASPEED_I2CD_INTR_ABNORMAL BIT(5) +#define ASPEED_I2CD_INTR_NORMAL_STOP BIT(4) +#define ASPEED_I2CD_INTR_ARBIT_LOSS BIT(3) +#define ASPEED_I2CD_INTR_RX_DONE BIT(2) +#define ASPEED_I2CD_INTR_TX_NAK BIT(1) +#define ASPEED_I2CD_INTR_TX_ACK BIT(0) +#define ASPEED_I2CD_INTR_ALL \ + (ASPEED_I2CD_INTR_SDA_DL_TIMEOUT | \ + ASPEED_I2CD_INTR_BUS_RECOVER_DONE | \ + ASPEED_I2CD_INTR_SCL_TIMEOUT | \ + ASPEED_I2CD_INTR_ABNORMAL | \ + ASPEED_I2CD_INTR_NORMAL_STOP | \ + ASPEED_I2CD_INTR_ARBIT_LOSS | \ + ASPEED_I2CD_INTR_RX_DONE | \ + ASPEED_I2CD_INTR_TX_NAK | \ + ASPEED_I2CD_INTR_TX_ACK) + +/* 0x14 : I2CD Command/Status Register */ +#define ASPEED_I2CD_SCL_LINE_STS BIT(18) +#define ASPEED_I2CD_SDA_LINE_STS BIT(17) +#define ASPEED_I2CD_BUS_BUSY_STS BIT(16) +#define ASPEED_I2CD_BUS_RECOVER_CMD BIT(11) + +/* Command Bit */ +#define ASPEED_I2CD_M_STOP_CMD BIT(5) +#define ASPEED_I2CD_M_S_RX_CMD_LAST BIT(4) +#define ASPEED_I2CD_M_RX_CMD BIT(3) +#define ASPEED_I2CD_S_TX_CMD BIT(2) +#define ASPEED_I2CD_M_TX_CMD BIT(1) +#define ASPEED_I2CD_M_START_CMD BIT(0) + +/* 0x18 : I2CD Slave Device Address Register */ +#define ASPEED_I2CD_DEV_ADDR_MASK GENMASK(6, 0) + +enum aspeed_i2c_master_state { + ASPEED_I2C_MASTER_START, + ASPEED_I2C_MASTER_TX_FIRST, + ASPEED_I2C_MASTER_TX, + ASPEED_I2C_MASTER_RX_FIRST, + ASPEED_I2C_MASTER_RX, + ASPEED_I2C_MASTER_STOP, + ASPEED_I2C_MASTER_INACTIVE, +}; + +enum aspeed_i2c_slave_state { + ASPEED_I2C_SLAVE_START, + ASPEED_I2C_SLAVE_READ_REQUESTED, + ASPEED_I2C_SLAVE_READ_PROCESSED, + ASPEED_I2C_SLAVE_WRITE_REQUESTED, + ASPEED_I2C_SLAVE_WRITE_RECEIVED, + ASPEED_I2C_SLAVE_STOP, +}; + +struct aspeed_i2c_bus { + struct i2c_adapter adap; + struct device *dev; + void __iomem *base; + /* Synchronizes I/O mem access to base. */ + spinlock_t lock; + struct completion cmd_complete; + unsigned long parent_clk_frequency; + u32 bus_frequency; + /* Transaction state. */ + enum aspeed_i2c_master_state master_state; + struct i2c_msg *msgs; + size_t buf_index; + size_t msgs_index; + size_t msgs_count; + bool send_stop; + int cmd_err; + /* Protected only by i2c_lock_bus */ + int master_xfer_result; +#if IS_ENABLED(CONFIG_I2C_SLAVE) + struct i2c_client *slave; + enum aspeed_i2c_slave_state slave_state; +#endif /* CONFIG_I2C_SLAVE */ +}; + +static int aspeed_i2c_reset(struct aspeed_i2c_bus *bus); + +static int aspeed_i2c_recover_bus(struct aspeed_i2c_bus *bus) +{ + unsigned long time_left, flags; + int ret = 0; + u32 command; + + spin_lock_irqsave(&bus->lock, flags); + command = readl(bus->base + ASPEED_I2C_CMD_REG); + + if (command & ASPEED_I2CD_SDA_LINE_STS) { + /* Bus is idle: no recovery needed. */ + if (command & ASPEED_I2CD_SCL_LINE_STS) + goto out; + dev_dbg(bus->dev, "SCL hung (state %x), attempting recovery\n", + command); + + reinit_completion(&bus->cmd_complete); + writel(ASPEED_I2CD_M_STOP_CMD, bus->base + ASPEED_I2C_CMD_REG); + spin_unlock_irqrestore(&bus->lock, flags); + + time_left = wait_for_completion_timeout( + &bus->cmd_complete, bus->adap.timeout); + + spin_lock_irqsave(&bus->lock, flags); + if (time_left == 0) + goto reset_out; + else if (bus->cmd_err) + goto reset_out; + /* Recovery failed. */ + else if (!(readl(bus->base + ASPEED_I2C_CMD_REG) & + ASPEED_I2CD_SCL_LINE_STS)) + goto reset_out; + /* Bus error. */ + } else { + dev_dbg(bus->dev, "SDA hung (state %x), attempting recovery\n", + command); + + reinit_completion(&bus->cmd_complete); + /* Writes 1 to 8 SCL clock cycles until SDA is released. */ + writel(ASPEED_I2CD_BUS_RECOVER_CMD, + bus->base + ASPEED_I2C_CMD_REG); + spin_unlock_irqrestore(&bus->lock, flags); + + time_left = wait_for_completion_timeout( + &bus->cmd_complete, bus->adap.timeout); + + spin_lock_irqsave(&bus->lock, flags); + if (time_left == 0) + goto reset_out; + else if (bus->cmd_err) + goto reset_out; + /* Recovery failed. */ + else if (!(readl(bus->base + ASPEED_I2C_CMD_REG) & + ASPEED_I2CD_SDA_LINE_STS)) + goto reset_out; + } + +out: + spin_unlock_irqrestore(&bus->lock, flags); + + return ret; + +reset_out: + spin_unlock_irqrestore(&bus->lock, flags); + + return aspeed_i2c_reset(bus); +} + +#if IS_ENABLED(CONFIG_I2C_SLAVE) +static bool aspeed_i2c_slave_irq(struct aspeed_i2c_bus *bus) +{ + u32 command, irq_status, status_ack = 0; + struct i2c_client *slave = bus->slave; + bool irq_handled = true; + u8 value; + + spin_lock(&bus->lock); + if (!slave) { + irq_handled = false; + goto out; + } + + command = readl(bus->base + ASPEED_I2C_CMD_REG); + irq_status = readl(bus->base + ASPEED_I2C_INTR_STS_REG); + + /* Slave was requested, restart state machine. */ + if (irq_status & ASPEED_I2CD_INTR_SLAVE_MATCH) { + status_ack |= ASPEED_I2CD_INTR_SLAVE_MATCH; + bus->slave_state = ASPEED_I2C_SLAVE_START; + } + + /* Slave is not currently active, irq was for someone else. */ + if (bus->slave_state == ASPEED_I2C_SLAVE_STOP) { + irq_handled = false; + goto out; + } + + dev_dbg(bus->dev, "slave irq status 0x%08x, cmd 0x%08x\n", + irq_status, command); + + /* Slave was sent something. */ + if (irq_status & ASPEED_I2CD_INTR_RX_DONE) { + value = readl(bus->base + ASPEED_I2C_BYTE_BUF_REG) >> 8; + /* Handle address frame. */ + if (bus->slave_state == ASPEED_I2C_SLAVE_START) { + if (value & 0x1) + bus->slave_state = + ASPEED_I2C_SLAVE_READ_REQUESTED; + else + bus->slave_state = + ASPEED_I2C_SLAVE_WRITE_REQUESTED; + } + status_ack |= ASPEED_I2CD_INTR_RX_DONE; + } + + /* Slave was asked to stop. */ + if (irq_status & ASPEED_I2CD_INTR_NORMAL_STOP) { + status_ack |= ASPEED_I2CD_INTR_NORMAL_STOP; + bus->slave_state = ASPEED_I2C_SLAVE_STOP; + } + if (irq_status & ASPEED_I2CD_INTR_TX_NAK) { + status_ack |= ASPEED_I2CD_INTR_TX_NAK; + bus->slave_state = ASPEED_I2C_SLAVE_STOP; + } + + switch (bus->slave_state) { + case ASPEED_I2C_SLAVE_READ_REQUESTED: + if (irq_status & ASPEED_I2CD_INTR_TX_ACK) + dev_err(bus->dev, "Unexpected ACK on read request.\n"); + bus->slave_state = ASPEED_I2C_SLAVE_READ_PROCESSED; + + i2c_slave_event(slave, I2C_SLAVE_READ_REQUESTED, &value); + writel(value, bus->base + ASPEED_I2C_BYTE_BUF_REG); + writel(ASPEED_I2CD_S_TX_CMD, bus->base + ASPEED_I2C_CMD_REG); + break; + case ASPEED_I2C_SLAVE_READ_PROCESSED: + status_ack |= ASPEED_I2CD_INTR_TX_ACK; + if (!(irq_status & ASPEED_I2CD_INTR_TX_ACK)) + dev_err(bus->dev, + "Expected ACK after processed read.\n"); + i2c_slave_event(slave, I2C_SLAVE_READ_PROCESSED, &value); + writel(value, bus->base + ASPEED_I2C_BYTE_BUF_REG); + writel(ASPEED_I2CD_S_TX_CMD, bus->base + ASPEED_I2C_CMD_REG); + break; + case ASPEED_I2C_SLAVE_WRITE_REQUESTED: + bus->slave_state = ASPEED_I2C_SLAVE_WRITE_RECEIVED; + i2c_slave_event(slave, I2C_SLAVE_WRITE_REQUESTED, &value); + break; + case ASPEED_I2C_SLAVE_WRITE_RECEIVED: + i2c_slave_event(slave, I2C_SLAVE_WRITE_RECEIVED, &value); + break; + case ASPEED_I2C_SLAVE_STOP: + i2c_slave_event(slave, I2C_SLAVE_STOP, &value); + break; + default: + dev_err(bus->dev, "unhandled slave_state: %d\n", + bus->slave_state); + break; + } + + if (status_ack != irq_status) + dev_err(bus->dev, + "irq handled != irq. expected %x, but was %x\n", + irq_status, status_ack); + writel(status_ack, bus->base + ASPEED_I2C_INTR_STS_REG); + +out: + spin_unlock(&bus->lock); + return irq_handled; +} +#endif /* CONFIG_I2C_SLAVE */ + +/* precondition: bus.lock has been acquired. */ +static void aspeed_i2c_do_start(struct aspeed_i2c_bus *bus) < |