Merge branch 'i2c-mux/for-next' of https://github.com/peda-r/i2c-mux into i2c/for-4.11
diff --git a/Documentation/devicetree/bindings/i2c/i2c-sh_mobile.txt b/Documentation/devicetree/bindings/i2c/i2c-sh_mobile.txt
index 7716acc..ae9c2a7 100644
--- a/Documentation/devicetree/bindings/i2c/i2c-sh_mobile.txt
+++ b/Documentation/devicetree/bindings/i2c/i2c-sh_mobile.txt
@@ -10,6 +10,7 @@
- "renesas,iic-r8a7793" (R-Car M2-N)
- "renesas,iic-r8a7794" (R-Car E2)
- "renesas,iic-r8a7795" (R-Car H3)
+ - "renesas,iic-r8a7796" (R-Car M3-W)
- "renesas,iic-sh73a0" (SH-Mobile AG5)
- "renesas,rcar-gen2-iic" (generic R-Car Gen2 compatible device)
- "renesas,rcar-gen3-iic" (generic R-Car Gen3 compatible device)
diff --git a/Documentation/devicetree/bindings/i2c/i2c-stm32.txt b/Documentation/devicetree/bindings/i2c/i2c-stm32.txt
new file mode 100644
index 0000000..78eaf7b
--- /dev/null
+++ b/Documentation/devicetree/bindings/i2c/i2c-stm32.txt
@@ -0,0 +1,33 @@
+* I2C controller embedded in STMicroelectronics STM32 I2C platform
+
+Required properties :
+- compatible : Must be "st,stm32f4-i2c"
+- reg : Offset and length of the register set for the device
+- interrupts : Must contain the interrupt id for I2C event and then the
+ interrupt id for I2C error.
+- resets: Must contain the phandle to the reset controller.
+- clocks: Must contain the input clock of the I2C instance.
+- A pinctrl state named "default" must be defined to set pins in mode of
+ operation for I2C transfer
+- #address-cells = <1>;
+- #size-cells = <0>;
+
+Optional properties :
+- clock-frequency : Desired I2C bus clock frequency in Hz. If not specified,
+ the default 100 kHz frequency will be used. As only Normal and Fast modes
+ are supported, possible values are 100000 and 400000.
+
+Example :
+
+ i2c@40005400 {
+ compatible = "st,stm32f4-i2c";
+ #address-cells = <1>;
+ #size-cells = <0>;
+ reg = <0x40005400 0x400>;
+ interrupts = <31>,
+ <32>;
+ resets = <&rcc 277>;
+ clocks = <&rcc 0 149>;
+ pinctrl-0 = <&i2c1_sda_pin>, <&i2c1_scl_pin>;
+ pinctrl-names = "default";
+ };
diff --git a/Documentation/i2c/busses/i2c-i801 b/Documentation/i2c/busses/i2c-i801
index 1bba38d..820d904 100644
--- a/Documentation/i2c/busses/i2c-i801
+++ b/Documentation/i2c/busses/i2c-i801
@@ -33,6 +33,7 @@
* Intel DNV (SOC)
* Intel Broxton (SOC)
* Intel Lewisburg (PCH)
+ * Intel Gemini Lake (SOC)
Datasheets: Publicly available at the Intel website
On Intel Patsburg and later chipsets, both the normal host SMBus controller
diff --git a/Documentation/i2c/muxes/i2c-mux-gpio b/Documentation/i2c/muxes/i2c-mux-gpio
index d4d91a5..7a8d7d2 100644
--- a/Documentation/i2c/muxes/i2c-mux-gpio
+++ b/Documentation/i2c/muxes/i2c-mux-gpio
@@ -1,11 +1,11 @@
-Kernel driver i2c-gpio-mux
+Kernel driver i2c-mux-gpio
Author: Peter Korsgaard <peter.korsgaard@barco.com>
Description
-----------
-i2c-gpio-mux is an i2c mux driver providing access to I2C bus segments
+i2c-mux-gpio is an i2c mux driver providing access to I2C bus segments
from a master I2C bus and a hardware MUX controlled through GPIO pins.
E.G.:
@@ -26,16 +26,16 @@
Usage
-----
-i2c-gpio-mux uses the platform bus, so you need to provide a struct
+i2c-mux-gpio uses the platform bus, so you need to provide a struct
platform_device with the platform_data pointing to a struct
-gpio_i2cmux_platform_data with the I2C adapter number of the master
+i2c_mux_gpio_platform_data with the I2C adapter number of the master
bus, the number of bus segments to create and the GPIO pins used
-to control it. See include/linux/i2c-gpio-mux.h for details.
+to control it. See include/linux/i2c-mux-gpio.h for details.
E.G. something like this for a MUX providing 4 bus segments
controlled through 3 GPIO pins:
-#include <linux/i2c-gpio-mux.h>
+#include <linux/i2c-mux-gpio.h>
#include <linux/platform_device.h>
static const unsigned myboard_gpiomux_gpios[] = {
@@ -46,7 +46,7 @@
0, 1, 2, 3
};
-static struct gpio_i2cmux_platform_data myboard_i2cmux_data = {
+static struct i2c_mux_gpio_platform_data myboard_i2cmux_data = {
.parent = 1,
.base_nr = 2, /* optional */
.values = myboard_gpiomux_values,
@@ -57,7 +57,7 @@
};
static struct platform_device myboard_i2cmux = {
- .name = "i2c-gpio-mux",
+ .name = "i2c-mux-gpio",
.id = 0,
.dev = {
.platform_data = &myboard_i2cmux_data,
@@ -66,14 +66,14 @@
If you don't know the absolute GPIO pin numbers at registration time,
you can instead provide a chip name (.chip_name) and relative GPIO pin
-numbers, and the i2c-gpio-mux driver will do the work for you,
+numbers, and the i2c-mux-gpio driver will do the work for you,
including deferred probing if the GPIO chip isn't immediately
available.
Device Registration
-------------------
-When registering your i2c-gpio-mux device, you should pass the number
+When registering your i2c-mux-gpio device, you should pass the number
of any GPIO pin it uses as the device ID. This guarantees that every
instance has a different ID.
diff --git a/drivers/i2c/busses/Kconfig b/drivers/i2c/busses/Kconfig
index 0cdc844..c64221d 100644
--- a/drivers/i2c/busses/Kconfig
+++ b/drivers/i2c/busses/Kconfig
@@ -128,6 +128,7 @@
DNV (SOC)
Broxton (SOC)
Lewisburg (PCH)
+ Gemini Lake (SOC)
This driver can also be built as a module. If so, the module
will be called i2c-i801.
@@ -886,6 +887,16 @@
This driver can also be built as module. If so, the module
will be called i2c-st.
+config I2C_STM32F4
+ tristate "STMicroelectronics STM32F4 I2C support"
+ depends on ARCH_STM32 || COMPILE_TEST
+ help
+ Enable this option to add support for STM32 I2C controller embedded
+ in STM32F4 SoCs.
+
+ This driver can also be built as module. If so, the module
+ will be called i2c-stm32f4.
+
config I2C_STU300
tristate "ST Microelectronics DDC I2C interface"
depends on MACH_U300
diff --git a/drivers/i2c/busses/Makefile b/drivers/i2c/busses/Makefile
index 1c1bac8..a2c6ff5 100644
--- a/drivers/i2c/busses/Makefile
+++ b/drivers/i2c/busses/Makefile
@@ -85,6 +85,7 @@
obj-$(CONFIG_I2C_SIMTEC) += i2c-simtec.o
obj-$(CONFIG_I2C_SIRF) += i2c-sirf.o
obj-$(CONFIG_I2C_ST) += i2c-st.o
+obj-$(CONFIG_I2C_STM32F4) += i2c-stm32f4.o
obj-$(CONFIG_I2C_STU300) += i2c-stu300.o
obj-$(CONFIG_I2C_SUN6I_P2WI) += i2c-sun6i-p2wi.o
obj-$(CONFIG_I2C_TEGRA) += i2c-tegra.o
diff --git a/drivers/i2c/busses/i2c-at91.c b/drivers/i2c/busses/i2c-at91.c
index 0b86c61..e4fcb0c 100644
--- a/drivers/i2c/busses/i2c-at91.c
+++ b/drivers/i2c/busses/i2c-at91.c
@@ -820,7 +820,7 @@ static u32 at91_twi_func(struct i2c_adapter *adapter)
| I2C_FUNC_SMBUS_READ_BLOCK_DATA;
}
-static struct i2c_algorithm at91_twi_algorithm = {
+static const struct i2c_algorithm at91_twi_algorithm = {
.master_xfer = at91_twi_xfer,
.functionality = at91_twi_func,
};
diff --git a/drivers/i2c/busses/i2c-bfin-twi.c b/drivers/i2c/busses/i2c-bfin-twi.c
index 29d00c4..9fe942b 100644
--- a/drivers/i2c/busses/i2c-bfin-twi.c
+++ b/drivers/i2c/busses/i2c-bfin-twi.c
@@ -563,7 +563,7 @@ static u32 bfin_twi_functionality(struct i2c_adapter *adap)
I2C_FUNC_I2C | I2C_FUNC_SMBUS_I2C_BLOCK;
}
-static struct i2c_algorithm bfin_twi_algorithm = {
+static const struct i2c_algorithm bfin_twi_algorithm = {
.master_xfer = bfin_twi_master_xfer,
.smbus_xfer = bfin_twi_smbus_xfer,
.functionality = bfin_twi_functionality,
diff --git a/drivers/i2c/busses/i2c-cros-ec-tunnel.c b/drivers/i2c/busses/i2c-cros-ec-tunnel.c
index 9b36a7b..eb76b76 100644
--- a/drivers/i2c/busses/i2c-cros-ec-tunnel.c
+++ b/drivers/i2c/busses/i2c-cros-ec-tunnel.c
@@ -154,8 +154,10 @@ static int ec_i2c_parse_response(const u8 *buf, struct i2c_msg i2c_msgs[],
resp = (const struct ec_response_i2c_passthru *)buf;
if (resp->i2c_status & EC_I2C_STATUS_TIMEOUT)
return -ETIMEDOUT;
+ else if (resp->i2c_status & EC_I2C_STATUS_NAK)
+ return -ENXIO;
else if (resp->i2c_status & EC_I2C_STATUS_ERROR)
- return -EREMOTEIO;
+ return -EIO;
/* Other side could send us back fewer messages, but not more */
if (resp->num_msgs > *num)
@@ -222,10 +224,8 @@ static int ec_i2c_xfer(struct i2c_adapter *adap, struct i2c_msg i2c_msgs[],
}
result = ec_i2c_parse_response(msg->data, i2c_msgs, &num);
- if (result < 0) {
- dev_err(dev, "Error parsing EC i2c message %d\n", result);
+ if (result < 0)
goto exit;
- }
/* Indicate success by saying how many messages were sent */
result = num;
diff --git a/drivers/i2c/busses/i2c-designware-core.c b/drivers/i2c/busses/i2c-designware-core.c
index 6d81c56..a62c14c 100644
--- a/drivers/i2c/busses/i2c-designware-core.c
+++ b/drivers/i2c/busses/i2c-designware-core.c
@@ -822,7 +822,7 @@ static u32 i2c_dw_func(struct i2c_adapter *adap)
return dev->functionality;
}
-static struct i2c_algorithm i2c_dw_algo = {
+static const struct i2c_algorithm i2c_dw_algo = {
.master_xfer = i2c_dw_xfer,
.functionality = i2c_dw_func,
};
diff --git a/drivers/i2c/busses/i2c-eg20t.c b/drivers/i2c/busses/i2c-eg20t.c
index 5ce71ce..bdeab01 100644
--- a/drivers/i2c/busses/i2c-eg20t.c
+++ b/drivers/i2c/busses/i2c-eg20t.c
@@ -715,7 +715,7 @@ static u32 pch_i2c_func(struct i2c_adapter *adap)
return I2C_FUNC_I2C | I2C_FUNC_SMBUS_EMUL | I2C_FUNC_10BIT_ADDR;
}
-static struct i2c_algorithm pch_algorithm = {
+static const struct i2c_algorithm pch_algorithm = {
.master_xfer = pch_i2c_xfer,
.functionality = pch_i2c_func
};
diff --git a/drivers/i2c/busses/i2c-emev2.c b/drivers/i2c/busses/i2c-emev2.c
index 96bb4e7..3129127 100644
--- a/drivers/i2c/busses/i2c-emev2.c
+++ b/drivers/i2c/busses/i2c-emev2.c
@@ -347,7 +347,7 @@ static int em_i2c_unreg_slave(struct i2c_client *slave)
return 0;
}
-static struct i2c_algorithm em_i2c_algo = {
+static const struct i2c_algorithm em_i2c_algo = {
.master_xfer = em_i2c_xfer,
.functionality = em_i2c_func,
.reg_slave = em_i2c_reg_slave,
diff --git a/drivers/i2c/busses/i2c-i801.c b/drivers/i2c/busses/i2c-i801.c
index e242db4..6484fa6 100644
--- a/drivers/i2c/busses/i2c-i801.c
+++ b/drivers/i2c/busses/i2c-i801.c
@@ -65,6 +65,7 @@
* Lewisburg (PCH) 0xa1a3 32 hard yes yes yes
* Lewisburg Supersku (PCH) 0xa223 32 hard yes yes yes
* Kaby Lake PCH-H (PCH) 0xa2a3 32 hard yes yes yes
+ * Gemini Lake (SOC) 0x31d4 32 hard yes yes yes
*
* Features supported by this driver:
* Software PEC no
@@ -213,6 +214,7 @@
#define PCI_DEVICE_ID_INTEL_BRASWELL_SMBUS 0x2292
#define PCI_DEVICE_ID_INTEL_DH89XXCC_SMBUS 0x2330
#define PCI_DEVICE_ID_INTEL_COLETOCREEK_SMBUS 0x23b0
+#define PCI_DEVICE_ID_INTEL_GEMINILAKE_SMBUS 0x31d4
#define PCI_DEVICE_ID_INTEL_5_3400_SERIES_SMBUS 0x3b30
#define PCI_DEVICE_ID_INTEL_BROXTON_SMBUS 0x5ad4
#define PCI_DEVICE_ID_INTEL_LYNXPOINT_SMBUS 0x8c22
@@ -1012,6 +1014,7 @@ static const struct pci_device_id i801_ids[] = {
{ PCI_DEVICE(PCI_VENDOR_ID_INTEL, PCI_DEVICE_ID_INTEL_WELLSBURG_SMBUS_MS1) },
{ PCI_DEVICE(PCI_VENDOR_ID_INTEL, PCI_DEVICE_ID_INTEL_WELLSBURG_SMBUS_MS2) },
{ PCI_DEVICE(PCI_VENDOR_ID_INTEL, PCI_DEVICE_ID_INTEL_COLETOCREEK_SMBUS) },
+ { PCI_DEVICE(PCI_VENDOR_ID_INTEL, PCI_DEVICE_ID_INTEL_GEMINILAKE_SMBUS) },
{ PCI_DEVICE(PCI_VENDOR_ID_INTEL, PCI_DEVICE_ID_INTEL_WILDCATPOINT_SMBUS) },
{ PCI_DEVICE(PCI_VENDOR_ID_INTEL, PCI_DEVICE_ID_INTEL_WILDCATPOINT_LP_SMBUS) },
{ PCI_DEVICE(PCI_VENDOR_ID_INTEL, PCI_DEVICE_ID_INTEL_BAYTRAIL_SMBUS) },
diff --git a/drivers/i2c/busses/i2c-imx-lpi2c.c b/drivers/i2c/busses/i2c-imx-lpi2c.c
index c62b7cd..934f548 100644
--- a/drivers/i2c/busses/i2c-imx-lpi2c.c
+++ b/drivers/i2c/busses/i2c-imx-lpi2c.c
@@ -537,7 +537,7 @@ static u32 lpi2c_imx_func(struct i2c_adapter *adapter)
I2C_FUNC_SMBUS_READ_BLOCK_DATA;
}
-static struct i2c_algorithm lpi2c_imx_algo = {
+static const struct i2c_algorithm lpi2c_imx_algo = {
.master_xfer = lpi2c_imx_xfer,
.functionality = lpi2c_imx_func,
};
diff --git a/drivers/i2c/busses/i2c-imx.c b/drivers/i2c/busses/i2c-imx.c
index 47fc1f1..95ed171 100644
--- a/drivers/i2c/busses/i2c-imx.c
+++ b/drivers/i2c/busses/i2c-imx.c
@@ -1037,7 +1037,7 @@ static u32 i2c_imx_func(struct i2c_adapter *adapter)
| I2C_FUNC_SMBUS_READ_BLOCK_DATA;
}
-static struct i2c_algorithm i2c_imx_algo = {
+static const struct i2c_algorithm i2c_imx_algo = {
.master_xfer = i2c_imx_xfer,
.functionality = i2c_imx_func,
};
diff --git a/drivers/i2c/busses/i2c-mv64xxx.c b/drivers/i2c/busses/i2c-mv64xxx.c
index b4dec08..a50bd68 100644
--- a/drivers/i2c/busses/i2c-mv64xxx.c
+++ b/drivers/i2c/busses/i2c-mv64xxx.c
@@ -977,11 +977,32 @@ mv64xxx_i2c_remove(struct platform_device *dev)
return 0;
}
+#ifdef CONFIG_PM
+static int mv64xxx_i2c_resume(struct device *dev)
+{
+ struct platform_device *pdev = to_platform_device(dev);
+ struct mv64xxx_i2c_data *drv_data = platform_get_drvdata(pdev);
+
+ mv64xxx_i2c_hw_init(drv_data);
+
+ return 0;
+}
+
+static const struct dev_pm_ops mv64xxx_i2c_pm = {
+ .resume = mv64xxx_i2c_resume,
+};
+
+#define mv64xxx_i2c_pm_ops (&mv64xxx_i2c_pm)
+#else
+#define mv64xxx_i2c_pm_ops NULL
+#endif
+
static struct platform_driver mv64xxx_i2c_driver = {
.probe = mv64xxx_i2c_probe,
.remove = mv64xxx_i2c_remove,
.driver = {
.name = MV64XXX_I2C_CTLR_NAME,
+ .pm = mv64xxx_i2c_pm_ops,
.of_match_table = mv64xxx_i2c_of_match_table,
},
};
diff --git a/drivers/i2c/busses/i2c-nforce2.c b/drivers/i2c/busses/i2c-nforce2.c
index 374b35e..3241bb9 100644
--- a/drivers/i2c/busses/i2c-nforce2.c
+++ b/drivers/i2c/busses/i2c-nforce2.c
@@ -296,7 +296,7 @@ static u32 nforce2_func(struct i2c_adapter *adapter)
I2C_FUNC_SMBUS_BLOCK_DATA : 0);
}
-static struct i2c_algorithm smbus_algorithm = {
+static const struct i2c_algorithm smbus_algorithm = {
.smbus_xfer = nforce2_access,
.functionality = nforce2_func,
};
diff --git a/drivers/i2c/busses/i2c-omap.c b/drivers/i2c/busses/i2c-omap.c
index c7da0c4..1ebb5e9 100644
--- a/drivers/i2c/busses/i2c-omap.c
+++ b/drivers/i2c/busses/i2c-omap.c
@@ -1504,7 +1504,7 @@ static int omap_i2c_runtime_resume(struct device *dev)
return 0;
}
-static struct dev_pm_ops omap_i2c_pm_ops = {
+static const struct dev_pm_ops omap_i2c_pm_ops = {
SET_RUNTIME_PM_OPS(omap_i2c_runtime_suspend,
omap_i2c_runtime_resume, NULL)
};
diff --git a/drivers/i2c/busses/i2c-riic.c b/drivers/i2c/busses/i2c-riic.c
index 6263ea8..8f11d34 100644
--- a/drivers/i2c/busses/i2c-riic.c
+++ b/drivers/i2c/busses/i2c-riic.c
@@ -80,6 +80,7 @@
#define ICIER_TEIE 0x40
#define ICIER_RIE 0x20
#define ICIER_NAKIE 0x10
+#define ICIER_SPIE 0x08
#define ICSR2_NACKF 0x10
@@ -216,11 +217,10 @@ static irqreturn_t riic_tend_isr(int irq, void *data)
return IRQ_NONE;
}
- if (riic->is_last || riic->err)
+ if (riic->is_last || riic->err) {
+ riic_clear_set_bit(riic, 0, ICIER_SPIE, RIIC_ICIER);
writeb(ICCR2_SP, riic->base + RIIC_ICCR2);
-
- writeb(0, riic->base + RIIC_ICIER);
- complete(&riic->msg_done);
+ }
return IRQ_HANDLED;
}
@@ -240,13 +240,13 @@ static irqreturn_t riic_rdrf_isr(int irq, void *data)
if (riic->bytes_left == 1) {
/* STOP must come before we set ACKBT! */
- if (riic->is_last)
+ if (riic->is_last) {
+ riic_clear_set_bit(riic, 0, ICIER_SPIE, RIIC_ICIER);
writeb(ICCR2_SP, riic->base + RIIC_ICCR2);
+ }
riic_clear_set_bit(riic, 0, ICMR3_ACKBT, RIIC_ICMR3);
- writeb(0, riic->base + RIIC_ICIER);
- complete(&riic->msg_done);
} else {
riic_clear_set_bit(riic, ICMR3_ACKBT, 0, RIIC_ICMR3);
}
@@ -259,6 +259,21 @@ static irqreturn_t riic_rdrf_isr(int irq, void *data)
return IRQ_HANDLED;
}
+static irqreturn_t riic_stop_isr(int irq, void *data)
+{
+ struct riic_dev *riic = data;
+
+ /* read back registers to confirm writes have fully propagated */
+ writeb(0, riic->base + RIIC_ICSR2);
+ readb(riic->base + RIIC_ICSR2);
+ writeb(0, riic->base + RIIC_ICIER);
+ readb(riic->base + RIIC_ICIER);
+
+ complete(&riic->msg_done);
+
+ return IRQ_HANDLED;
+}
+
static u32 riic_func(struct i2c_adapter *adap)
{
return I2C_FUNC_I2C | I2C_FUNC_SMBUS_EMUL;
@@ -326,6 +341,7 @@ static struct riic_irq_desc riic_irqs[] = {
{ .res_num = 0, .isr = riic_tend_isr, .name = "riic-tend" },
{ .res_num = 1, .isr = riic_rdrf_isr, .name = "riic-rdrf" },
{ .res_num = 2, .isr = riic_tdre_isr, .name = "riic-tdre" },
+ { .res_num = 3, .isr = riic_stop_isr, .name = "riic-stop" },
{ .res_num = 5, .isr = riic_tend_isr, .name = "riic-nack" },
};
diff --git a/drivers/i2c/busses/i2c-robotfuzz-osif.c b/drivers/i2c/busses/i2c-robotfuzz-osif.c
index 89d8b41..9c0f52b 100644
--- a/drivers/i2c/busses/i2c-robotfuzz-osif.c
+++ b/drivers/i2c/busses/i2c-robotfuzz-osif.c
@@ -117,7 +117,7 @@ static u32 osif_func(struct i2c_adapter *adapter)
return I2C_FUNC_I2C | I2C_FUNC_SMBUS_EMUL;
}
-static struct i2c_algorithm osif_algorithm = {
+static const struct i2c_algorithm osif_algorithm = {
.master_xfer = osif_xfer,
.functionality = osif_func,
};
diff --git a/drivers/i2c/busses/i2c-sh_mobile.c b/drivers/i2c/busses/i2c-sh_mobile.c
index 3d9ebe6..3d75593 100644
--- a/drivers/i2c/busses/i2c-sh_mobile.c
+++ b/drivers/i2c/busses/i2c-sh_mobile.c
@@ -781,7 +781,7 @@ static u32 sh_mobile_i2c_func(struct i2c_adapter *adapter)
return I2C_FUNC_I2C | I2C_FUNC_SMBUS_EMUL | I2C_FUNC_PROTOCOL_MANGLING;
}
-static struct i2c_algorithm sh_mobile_i2c_algorithm = {
+static const struct i2c_algorithm sh_mobile_i2c_algorithm = {
.functionality = sh_mobile_i2c_func,
.master_xfer = sh_mobile_i2c_xfer,
};
diff --git a/drivers/i2c/busses/i2c-st.c b/drivers/i2c/busses/i2c-st.c
index 1371547..1eb9fa8 100644
--- a/drivers/i2c/busses/i2c-st.c
+++ b/drivers/i2c/busses/i2c-st.c
@@ -776,7 +776,7 @@ static u32 st_i2c_func(struct i2c_adapter *adap)
return I2C_FUNC_I2C | I2C_FUNC_SMBUS_EMUL;
}
-static struct i2c_algorithm st_i2c_algo = {
+static const struct i2c_algorithm st_i2c_algo = {
.master_xfer = st_i2c_xfer,
.functionality = st_i2c_func,
};
diff --git a/drivers/i2c/busses/i2c-stm32f4.c b/drivers/i2c/busses/i2c-stm32f4.c
new file mode 100644
index 0000000..f9dd7e8
--- /dev/null
+++ b/drivers/i2c/busses/i2c-stm32f4.c
@@ -0,0 +1,897 @@
+/*
+ * Driver for STMicroelectronics STM32 I2C controller
+ *
+ * This I2C controller is described in the STM32F429/439 Soc reference manual.
+ * Please see below a link to the documentation:
+ * http://www.st.com/resource/en/reference_manual/DM00031020.pdf
+ *
+ * Copyright (C) M'boumba Cedric Madianga 2016
+ * Author: M'boumba Cedric Madianga <cedric.madianga@gmail.com>
+ *
+ * This driver is based on i2c-st.c
+ *
+ * License terms: GNU General Public License (GPL), version 2
+ */
+
+#include <linux/clk.h>
+#include <linux/delay.h>
+#include <linux/err.h>
+#include <linux/i2c.h>
+#include <linux/interrupt.h>
+#include <linux/io.h>
+#include <linux/iopoll.h>
+#include <linux/module.h>
+#include <linux/of_address.h>
+#include <linux/of_irq.h>
+#include <linux/of.h>
+#include <linux/platform_device.h>
+#include <linux/reset.h>
+
+/* STM32F4 I2C offset registers */
+#define STM32F4_I2C_CR1 0x00
+#define STM32F4_I2C_CR2 0x04
+#define STM32F4_I2C_DR 0x10
+#define STM32F4_I2C_SR1 0x14
+#define STM32F4_I2C_SR2 0x18
+#define STM32F4_I2C_CCR 0x1C
+#define STM32F4_I2C_TRISE 0x20
+#define STM32F4_I2C_FLTR 0x24
+
+/* STM32F4 I2C control 1*/
+#define STM32F4_I2C_CR1_POS BIT(11)
+#define STM32F4_I2C_CR1_ACK BIT(10)
+#define STM32F4_I2C_CR1_STOP BIT(9)
+#define STM32F4_I2C_CR1_START BIT(8)
+#define STM32F4_I2C_CR1_PE BIT(0)
+
+/* STM32F4 I2C control 2 */
+#define STM32F4_I2C_CR2_FREQ_MASK GENMASK(5, 0)
+#define STM32F4_I2C_CR2_FREQ(n) ((n) & STM32F4_I2C_CR2_FREQ_MASK)
+#define STM32F4_I2C_CR2_ITBUFEN BIT(10)
+#define STM32F4_I2C_CR2_ITEVTEN BIT(9)
+#define STM32F4_I2C_CR2_ITERREN BIT(8)
+#define STM32F4_I2C_CR2_IRQ_MASK (STM32F4_I2C_CR2_ITBUFEN | \
+ STM32F4_I2C_CR2_ITEVTEN | \
+ STM32F4_I2C_CR2_ITERREN)
+
+/* STM32F4 I2C Status 1 */
+#define STM32F4_I2C_SR1_AF BIT(10)
+#define STM32F4_I2C_SR1_ARLO BIT(9)
+#define STM32F4_I2C_SR1_BERR BIT(8)
+#define STM32F4_I2C_SR1_TXE BIT(7)
+#define STM32F4_I2C_SR1_RXNE BIT(6)
+#define STM32F4_I2C_SR1_BTF BIT(2)
+#define STM32F4_I2C_SR1_ADDR BIT(1)
+#define STM32F4_I2C_SR1_SB BIT(0)
+#define STM32F4_I2C_SR1_ITEVTEN_MASK (STM32F4_I2C_SR1_BTF | \
+ STM32F4_I2C_SR1_ADDR | \
+ STM32F4_I2C_SR1_SB)
+#define STM32F4_I2C_SR1_ITBUFEN_MASK (STM32F4_I2C_SR1_TXE | \
+ STM32F4_I2C_SR1_RXNE)
+#define STM32F4_I2C_SR1_ITERREN_MASK (STM32F4_I2C_SR1_AF | \
+ STM32F4_I2C_SR1_ARLO | \
+ STM32F4_I2C_SR1_BERR)
+
+/* STM32F4 I2C Status 2 */
+#define STM32F4_I2C_SR2_BUSY BIT(1)
+
+/* STM32F4 I2C Control Clock */
+#define STM32F4_I2C_CCR_CCR_MASK GENMASK(11, 0)
+#define STM32F4_I2C_CCR_CCR(n) ((n) & STM32F4_I2C_CCR_CCR_MASK)
+#define STM32F4_I2C_CCR_FS BIT(15)
+#define STM32F4_I2C_CCR_DUTY BIT(14)
+
+/* STM32F4 I2C Trise */
+#define STM32F4_I2C_TRISE_VALUE_MASK GENMASK(5, 0)
+#define STM32F4_I2C_TRISE_VALUE(n) ((n) & STM32F4_I2C_TRISE_VALUE_MASK)
+
+#define STM32F4_I2C_MIN_STANDARD_FREQ 2U
+#define STM32F4_I2C_MIN_FAST_FREQ 6U
+#define STM32F4_I2C_MAX_FREQ 46U
+#define HZ_TO_MHZ 1000000
+
+enum stm32f4_i2c_speed {
+ STM32F4_I2C_SPEED_STANDARD, /* 100 kHz */
+ STM32F4_I2C_SPEED_FAST, /* 400 kHz */
+ STM32F4_I2C_SPEED_END,
+};
+
+/**
+ * struct stm32f4_i2c_msg - client specific data
+ * @addr: 8-bit slave addr, including r/w bit
+ * @count: number of bytes to be transferred
+ * @buf: data buffer
+ * @result: result of the transfer
+ * @stop: last I2C msg to be sent, i.e. STOP to be generated
+ */
+struct stm32f4_i2c_msg {
+ u8 addr;
+ u32 count;
+ u8 *buf;
+ int result;
+ bool stop;
+};
+
+/**
+ * struct stm32f4_i2c_dev - private data of the controller
+ * @adap: I2C adapter for this controller
+ * @dev: device for this controller
+ * @base: virtual memory area
+ * @complete: completion of I2C message
+ * @clk: hw i2c clock
+ * @speed: I2C clock frequency of the controller. Standard or Fast are supported
+ * @parent_rate: I2C clock parent rate in MHz
+ * @msg: I2C transfer information
+ */
+struct stm32f4_i2c_dev {
+ struct i2c_adapter adap;
+ struct device *dev;
+ void __iomem *base;
+ struct completion complete;
+ struct clk *clk;
+ int speed;
+ int parent_rate;
+ struct stm32f4_i2c_msg msg;
+};
+
+static inline void stm32f4_i2c_set_bits(void __iomem *reg, u32 mask)
+{
+ writel_relaxed(readl_relaxed(reg) | mask, reg);
+}
+
+static inline void stm32f4_i2c_clr_bits(void __iomem *reg, u32 mask)
+{
+ writel_relaxed(readl_relaxed(reg) & ~mask, reg);
+}
+
+static void stm32f4_i2c_disable_irq(struct stm32f4_i2c_dev *i2c_dev)
+{
+ void __iomem *reg = i2c_dev->base + STM32F4_I2C_CR2;
+
+ stm32f4_i2c_clr_bits(reg, STM32F4_I2C_CR2_IRQ_MASK);
+}
+
+static int stm32f4_i2c_set_periph_clk_freq(struct stm32f4_i2c_dev *i2c_dev)
+{
+ u32 freq;
+ u32 cr2 = 0;
+
+ i2c_dev->parent_rate = clk_get_rate(i2c_dev->clk);
+ freq = DIV_ROUND_UP(i2c_dev->parent_rate, HZ_TO_MHZ);
+
+ if (i2c_dev->speed == STM32F4_I2C_SPEED_STANDARD) {
+ /*
+ * To reach 100 kHz, the parent clk frequency should be between
+ * a minimum value of 2 MHz and a maximum value of 46 MHz due
+ * to hardware limitation
+ */
+ if (freq < STM32F4_I2C_MIN_STANDARD_FREQ ||
+ freq > STM32F4_I2C_MAX_FREQ) {
+ dev_err(i2c_dev->dev,
+ "bad parent clk freq for standard mode\n");
+ return -EINVAL;
+ }
+ } else {
+ /*
+ * To be as close as possible to 400 kHz, the parent clk
+ * frequency should be between a minimum value of 6 MHz and a
+ * maximum value of 46 MHz due to hardware limitation
+ */
+ if (freq < STM32F4_I2C_MIN_FAST_FREQ ||
+ freq > STM32F4_I2C_MAX_FREQ) {
+ dev_err(i2c_dev->dev,
+ "bad parent clk freq for fast mode\n");
+ return -EINVAL;
+ }
+ }
+
+ cr2 |= STM32F4_I2C_CR2_FREQ(freq);
+ writel_relaxed(cr2, i2c_dev->base + STM32F4_I2C_CR2);
+
+ return 0;
+}
+
+static void stm32f4_i2c_set_rise_time(struct stm32f4_i2c_dev *i2c_dev)
+{
+ u32 freq = DIV_ROUND_UP(i2c_dev->parent_rate, HZ_TO_MHZ);
+ u32 trise;
+
+ /*
+ * These bits must be programmed with the maximum SCL rise time given in
+ * the I2C bus specification, incremented by 1.
+ *
+ * In standard mode, the maximum allowed SCL rise time is 1000 ns.
+ * If, in the I2C_CR2 register, the value of FREQ[5:0] bits is equal to
+ * 0x08 so period = 125 ns therefore the TRISE[5:0] bits must be
+ * programmed with 0x9. (1000 ns / 125 ns + 1)
+ * So, for I2C standard mode TRISE = FREQ[5:0] + 1
+ *
+ * In fast mode, the maximum allowed SCL rise time is 300 ns.
+ * If, in the I2C_CR2 register, the value of FREQ[5:0] bits is equal to
+ * 0x08 so period = 125 ns therefore the TRISE[5:0] bits must be
+ * programmed with 0x3. (300 ns / 125 ns + 1)
+ * So, for I2C fast mode TRISE = FREQ[5:0] * 300 / 1000 + 1
+ *
+ * Function stm32f4_i2c_set_periph_clk_freq made sure that parent rate
+ * is not higher than 46 MHz . As a result trise is at most 4 bits wide
+ * and so fits into the TRISE bits [5:0].
+ */
+ if (i2c_dev->speed == STM32F4_I2C_SPEED_STANDARD)
+ trise = freq + 1;
+ else
+ trise = freq * 3 / 10 + 1;
+
+ writel_relaxed(STM32F4_I2C_TRISE_VALUE(trise),
+ i2c_dev->base + STM32F4_I2C_TRISE);
+}
+
+static void stm32f4_i2c_set_speed_mode(struct stm32f4_i2c_dev *i2c_dev)
+{
+ u32 val;
+ u32 ccr = 0;
+
+ if (i2c_dev->speed == STM32F4_I2C_SPEED_STANDARD) {
+ /*
+ * In standard mode:
+ * t_scl_high = t_scl_low = CCR * I2C parent clk period
+ * So to reach 100 kHz, we have:
+ * CCR = I2C parent rate / 100 kHz >> 1
+ *
+ * For example with parent rate = 2 MHz:
+ * CCR = 2000000 / (100000 << 1) = 10
+ * t_scl_high = t_scl_low = 10 * (1 / 2000000) = 5000 ns
+ * t_scl_high + t_scl_low = 10000 ns so 100 kHz is reached
+ *
+ * Function stm32f4_i2c_set_periph_clk_freq made sure that
+ * parent rate is not higher than 46 MHz . As a result val
+ * is at most 8 bits wide and so fits into the CCR bits [11:0].
+ */
+ val = i2c_dev->parent_rate / (100000 << 1);
+ } else {
+ /*
+ * In fast mode, we compute CCR with duty = 0 as with low
+ * frequencies we are not able to reach 400 kHz.
+ * In that case:
+ * t_scl_high = CCR * I2C parent clk period
+ * t_scl_low = 2 * CCR * I2C parent clk period
+ * So, CCR = I2C parent rate / (400 kHz * 3)
+ *
+ * For example with parent rate = 6 MHz:
+ * CCR = 6000000 / (400000 * 3) = 5
+ * t_scl_high = 5 * (1 / 6000000) = 833 ns > 600 ns
+ * t_scl_low = 2 * 5 * (1 / 6000000) = 1667 ns > 1300 ns
+ * t_scl_high + t_scl_low = 2500 ns so 400 kHz is reached
+ *
+ * Function stm32f4_i2c_set_periph_clk_freq made sure that
+ * parent rate is not higher than 46 MHz . As a result val
+ * is at most 6 bits wide and so fits into the CCR bits [11:0].
+ */
+ val = DIV_ROUND_UP(i2c_dev->parent_rate, 400000 * 3);
+
+ /* Select Fast mode */
+ ccr |= STM32F4_I2C_CCR_FS;
+ }
+
+ ccr |= STM32F4_I2C_CCR_CCR(val);
+ writel_relaxed(ccr, i2c_dev->base + STM32F4_I2C_CCR);
+}
+
+/**
+ * stm32f4_i2c_hw_config() - Prepare I2C block
+ * @i2c_dev: Controller's private data
+ */
+static int stm32f4_i2c_hw_config(struct stm32f4_i2c_dev *i2c_dev)
+{
+ int ret;
+
+ ret = stm32f4_i2c_set_periph_clk_freq(i2c_dev);
+ if (ret)
+ return ret;
+
+ stm32f4_i2c_set_rise_time(i2c_dev);
+
+ stm32f4_i2c_set_speed_mode(i2c_dev);
+
+ /* Enable I2C */
+ writel_relaxed(STM32F4_I2C_CR1_PE, i2c_dev->base + STM32F4_I2C_CR1);
+
+ return 0;
+}
+
+static int stm32f4_i2c_wait_free_bus(struct stm32f4_i2c_dev *i2c_dev)
+{
+ u32 status;
+ int ret;
+
+ ret = readl_relaxed_poll_timeout(i2c_dev->base + STM32F4_I2C_SR2,
+ status,
+ !(status & STM32F4_I2C_SR2_BUSY),
+ 10, 1000);
+ if (ret) {
+ dev_dbg(i2c_dev->dev, "bus not free\n");
+ ret = -EBUSY;
+ }
+
+ return ret;
+}
+
+/**
+ * stm32f4_i2c_write_ byte() - Write a byte in the data register
+ * @i2c_dev: Controller's private data
+ * @byte: Data to write in the register
+ */
+static void stm32f4_i2c_write_byte(struct stm32f4_i2c_dev *i2c_dev, u8 byte)
+{
+ writel_relaxed(byte, i2c_dev->base + STM32F4_I2C_DR);
+}
+
+/**
+ * stm32f4_i2c_write_msg() - Fill the data register in write mode
+ * @i2c_dev: Controller's private data
+ *
+ * This function fills the data register with I2C transfer buffer
+ */
+static void stm32f4_i2c_write_msg(struct stm32f4_i2c_dev *i2c_dev)
+{
+ struct stm32f4_i2c_msg *msg = &i2c_dev->msg;
+
+ stm32f4_i2c_write_byte(i2c_dev, *msg->buf++);
+ msg->count--;
+}
+
+static void stm32f4_i2c_read_msg(struct stm32f4_i2c_dev *i2c_dev)
+{
+ struct stm32f4_i2c_msg *msg = &i2c_dev->msg;
+ u32 rbuf;
+
+ rbuf = readl_relaxed(i2c_dev->base + STM32F4_I2C_DR);
+ *msg->buf++ = rbuf;
+ msg->count--;
+}
+
+static void stm32f4_i2c_terminate_xfer(struct stm32f4_i2c_dev *i2c_dev)
+{
+ struct stm32f4_i2c_msg *msg = &i2c_dev->msg;
+ void __iomem *reg = i2c_dev->base + STM32F4_I2C_CR2;
+
+ stm32f4_i2c_disable_irq(i2c_dev);
+
+ reg = i2c_dev->base + STM32F4_I2C_CR1;
+ if (msg->stop)
+ stm32f4_i2c_set_bits(reg, STM32F4_I2C_CR1_STOP);
+ else
+ stm32f4_i2c_set_bits(reg, STM32F4_I2C_CR1_START);
+
+ complete(&i2c_dev->complete);
+}
+
+/**
+ * stm32f4_i2c_handle_write() - Handle FIFO empty interrupt in case of write
+ * @i2c_dev: Controller's private data
+ */
+static void stm32f4_i2c_handle_write(struct stm32f4_i2c_dev *i2c_dev)
+{
+ struct stm32f4_i2c_msg *msg = &i2c_dev->msg;
+ void __iomem *reg = i2c_dev->base + STM32F4_I2C_CR2;
+
+ if (msg->count) {
+ stm32f4_i2c_write_msg(i2c_dev);
+ if (!msg->count) {
+ /*
+ * Disable buffer interrupts for RX not empty and TX
+ * empty events
+ */
+ stm32f4_i2c_clr_bits(reg, STM32F4_I2C_CR2_ITBUFEN);
+ }
+ } else {
+ stm32f4_i2c_terminate_xfer(i2c_dev);
+ }
+}
+
+/**
+ * stm32f4_i2c_handle_read() - Handle FIFO empty interrupt in case of read
+ * @i2c_dev: Controller's private data
+ *
+ * This function is called when a new data is received in data register
+ */
+static void stm32f4_i2c_handle_read(struct stm32f4_i2c_dev *i2c_dev)
+{
+ struct stm32f4_i2c_msg *msg = &i2c_dev->msg;
+ void __iomem *reg = i2c_dev->base + STM32F4_I2C_CR2;
+
+ switch (msg->count) {
+ case 1:
+ stm32f4_i2c_disable_irq(i2c_dev);
+ stm32f4_i2c_read_msg(i2c_dev);
+ complete(&i2c_dev->complete);
+ break;
+ /*
+ * For 2-byte reception, 3-byte reception and for Data N-2, N-1 and N
+ * for N-byte reception with N > 3, we do not have to read the data
+ * register when RX not empty event occurs as we have to wait for byte
+ * transferred finished event before reading data.
+ * So, here we just disable buffer interrupt in order to avoid another
+ * system preemption due to RX not empty event.
+ */
+ case 2:
+ case 3:
+ stm32f4_i2c_clr_bits(reg, STM32F4_I2C_CR2_ITBUFEN);
+ break;
+ /*
+ * For N byte reception with N > 3 we directly read data register
+ * until N-2 data.
+ */
+ default:
+ stm32f4_i2c_read_msg(i2c_dev);
+ }
+}
+
+/**
+ * stm32f4_i2c_handle_rx_done() - Handle byte transfer finished interrupt
+ * in case of read
+ * @i2c_dev: Controller's private data
+ *
+ * This function is called when a new data is received in the shift register
+ * but data register has not been read yet.
+ */
+static void stm32f4_i2c_handle_rx_done(struct stm32f4_i2c_dev *i2c_dev)
+{
+ struct stm32f4_i2c_msg *msg = &i2c_dev->msg;
+ void __iomem *reg;
+ u32 mask;
+ int i;
+
+ switch (msg->count) {
+ case 2:
+ /*
+ * In order to correctly send the Stop or Repeated Start
+ * condition on the I2C bus, the STOP/START bit has to be set
+ * before reading the last two bytes (data N-1 and N).
+ * After that, we could read the last two bytes, disable
+ * remaining interrupts and notify the end of xfer to the
+ * client
+ */
+ reg = i2c_dev->base + STM32F4_I2C_CR1;
+ if (msg->stop)
+ stm32f4_i2c_set_bits(reg, STM32F4_I2C_CR1_STOP);
+ else
+ stm32f4_i2c_set_bits(reg, STM32F4_I2C_CR1_START);
+
+ for (i = 2; i > 0; i--)
+ stm32f4_i2c_read_msg(i2c_dev);
+
+ reg = i2c_dev->base + STM32F4_I2C_CR2;
+ mask = STM32F4_I2C_CR2_ITEVTEN | STM32F4_I2C_CR2_ITERREN;
+ stm32f4_i2c_clr_bits(reg, mask);
+
+ complete(&i2c_dev->complete);
+ break;
+ case 3:
+ /*
+ * In order to correctly generate the NACK pulse after the last
+ * received data byte, we have to enable NACK before reading N-2
+ * data
+ */
+ reg = i2c_dev->base + STM32F4_I2C_CR1;
+ stm32f4_i2c_clr_bits(reg, STM32F4_I2C_CR1_ACK);
+ stm32f4_i2c_read_msg(i2c_dev);
+ break;
+ default:
+ stm32f4_i2c_read_msg(i2c_dev);
+ }
+}
+
+/**
+ * stm32f4_i2c_handle_rx_addr() - Handle address matched interrupt in case of
+ * master receiver
+ * @i2c_dev: Controller's private data
+ */
+static void stm32f4_i2c_handle_rx_addr(struct stm32f4_i2c_dev *i2c_dev)
+{
+ struct stm32f4_i2c_msg *msg = &i2c_dev->msg;
+ u32 cr1;
+
+ switch (msg->count) {
+ case 0:
+ stm32f4_i2c_terminate_xfer(i2c_dev);
+
+ /* Clear ADDR flag */
+ readl_relaxed(i2c_dev->base + STM32F4_I2C_SR2);
+ break;
+ case 1:
+ /*
+ * Single byte reception:
+ * Enable NACK and reset POS (Acknowledge position).
+ * Then, clear ADDR flag and set STOP or RepSTART.
+ * In that way, the NACK and STOP or RepStart pulses will be
+ * sent as soon as the byte will be received in shift register
+ */
+ cr1 = readl_relaxed(i2c_dev->base + STM32F4_I2C_CR1);
+ cr1 &= ~(STM32F4_I2C_CR1_ACK | STM32F4_I2C_CR1_POS);
+ writel_relaxed(cr1, i2c_dev->base + STM32F4_I2C_CR1);
+
+ readl_relaxed(i2c_dev->base + STM32F4_I2C_SR2);
+
+ if (msg->stop)
+ cr1 |= STM32F4_I2C_CR1_STOP;
+ else
+ cr1 |= STM32F4_I2C_CR1_START;
+ writel_relaxed(cr1, i2c_dev->base + STM32F4_I2C_CR1);
+ break;
+ case 2:
+ /*
+ * 2-byte reception:
+ * Enable NACK, set POS (NACK position) and clear ADDR flag.
+ * In that way, NACK will be sent for the next byte which will
+ * be received in the shift register instead of the current
+ * one.
+ */
+ cr1 = readl_relaxed(i2c_dev->base + STM32F4_I2C_CR1);
+ cr1 &= ~STM32F4_I2C_CR1_ACK;
+ cr1 |= STM32F4_I2C_CR1_POS;
+ writel_relaxed(cr1, i2c_dev->base + STM32F4_I2C_CR1);
+
+ readl_relaxed(i2c_dev->base + STM32F4_I2C_SR2);
+ break;
+
+ default:
+ /*
+ * N-byte reception:
+ * Enable ACK, reset POS (ACK postion) and clear ADDR flag.
+ * In that way, ACK will be sent as soon as the current byte
+ * will be received in the shift register
+ */
+ cr1 = readl_relaxed(i2c_dev->base + STM32F4_I2C_CR1);
+ cr1 |= STM32F4_I2C_CR1_ACK;
+ cr1 &= ~STM32F4_I2C_CR1_POS;
+ writel_relaxed(cr1, i2c_dev->base + STM32F4_I2C_CR1);
+
+ readl_relaxed(i2c_dev->base + STM32F4_I2C_SR2);
+ break;
+ }
+}
+
+/**
+ * stm32f4_i2c_isr_event() - Interrupt routine for I2C bus event
+ * @irq: interrupt number
+ * @data: Controller's private data
+ */
+static irqreturn_t stm32f4_i2c_isr_event(int irq, void *data)
+{
+ struct stm32f4_i2c_dev *i2c_dev = data;
+ struct stm32f4_i2c_msg *msg = &i2c_dev->msg;
+ u32 possible_status = STM32F4_I2C_SR1_ITEVTEN_MASK;
+ u32 status, ien, event, cr2;
+
+ cr2 = readl_relaxed(i2c_dev->base + STM32F4_I2C_CR2);
+ ien = cr2 & STM32F4_I2C_CR2_IRQ_MASK;
+
+ /* Update possible_status if buffer interrupt is enabled */
+ if (ien & STM32F4_I2C_CR2_ITBUFEN)
+ possible_status |= STM32F4_I2C_SR1_ITBUFEN_MASK;
+
+ status = readl_relaxed(i2c_dev->base + STM32F4_I2C_SR1);
+ event = status & possible_status;
+ if (!event) {
+ dev_dbg(i2c_dev->dev,
+ "spurious evt irq (status=0x%08x, ien=0x%08x)\n",
+ status, ien);
+ return IRQ_NONE;
+ }
+
+ /* Start condition generated */
+ if (event & STM32F4_I2C_SR1_SB)
+ stm32f4_i2c_write_byte(i2c_dev, msg->addr);
+
+ /* I2C Address sent */
+ if (event & STM32F4_I2C_SR1_ADDR) {
+ if (msg->addr & I2C_M_RD)
+ stm32f4_i2c_handle_rx_addr(i2c_dev);
+ else
+ readl_relaxed(i2c_dev->base + STM32F4_I2C_SR2);
+
+ /*
+ * Enable buffer interrupts for RX not empty and TX empty
+ * events
+ */
+ cr2 |= STM32F4_I2C_CR2_ITBUFEN;
+ writel_relaxed(cr2, i2c_dev->base + STM32F4_I2C_CR2);
+ }
+
+ /* TX empty */
+ if ((event & STM32F4_I2C_SR1_TXE) && !(msg->addr & I2C_M_RD))
+ stm32f4_i2c_handle_write(i2c_dev);
+
+ /* RX not empty */
+ if ((event & STM32F4_I2C_SR1_RXNE) && (msg->addr & I2C_M_RD))
+ stm32f4_i2c_handle_read(i2c_dev);
+
+ /*
+ * The BTF (Byte Transfer finished) event occurs when:
+ * - in reception : a new byte is received in the shift register
+ * but the previous byte has not been read yet from data register
+ * - in transmission: a new byte should be sent but the data register
+ * has not been written yet
+ */
+ if (event & STM32F4_I2C_SR1_BTF) {
+ if (msg->addr & I2C_M_RD)
+ stm32f4_i2c_handle_rx_done(i2c_dev);
+ else
+ stm32f4_i2c_handle_write(i2c_dev);
+ }
+
+ return IRQ_HANDLED;
+}
+
+/**
+ * stm32f4_i2c_isr_error() - Interrupt routine for I2C bus error
+ * @irq: interrupt number
+ * @data: Controller's private data
+ */
+static irqreturn_t stm32f4_i2c_isr_error(int irq, void *data)
+{
+ struct stm32f4_i2c_dev *i2c_dev = data;
+ struct stm32f4_i2c_msg *msg = &i2c_dev->msg;
+ void __iomem *reg;
+ u32 status;
+
+ status = readl_relaxed(i2c_dev->base + STM32F4_I2C_SR1);
+
+ /* Arbitration lost */
+ if (status & STM32F4_I2C_SR1_ARLO) {
+ status &= ~STM32F4_I2C_SR1_ARLO;
+ writel_relaxed(status, i2c_dev->base + STM32F4_I2C_SR1);
+ msg->result = -EAGAIN;
+ }
+
+ /*
+ * Acknowledge failure:
+ * In master transmitter mode a Stop must be generated by software
+ */
+ if (status & STM32F4_I2C_SR1_AF) {
+ if (!(msg->addr & I2C_M_RD)) {
+ reg = i2c_dev->base + STM32F4_I2C_CR1;
+ stm32f4_i2c_set_bits(reg, STM32F4_I2C_CR1_STOP);
+ }
+ status &= ~STM32F4_I2C_SR1_AF;
+ writel_relaxed(status, i2c_dev->base + STM32F4_I2C_SR1);
+ msg->result = -EIO;
+ }
+
+ /* Bus error */
+ if (status & STM32F4_I2C_SR1_BERR) {
+ status &= ~STM32F4_I2C_SR1_BERR;
+ writel_relaxed(status, i2c_dev->base + STM32F4_I2C_SR1);
+ msg->result = -EIO;
+ }
+
+ stm32f4_i2c_disable_irq(i2c_dev);
+ complete(&i2c_dev->complete);
+
+ return IRQ_HANDLED;
+}
+
+/**
+ * stm32f4_i2c_xfer_msg() - Transfer a single I2C message
+ * @i2c_dev: Controller's private data
+ * @msg: I2C message to transfer
+ * @is_first: first message of the sequence
+ * @is_last: last message of the sequence
+ */
+static int stm32f4_i2c_xfer_msg(struct stm32f4_i2c_dev *i2c_dev,
+ struct i2c_msg *msg, bool is_first,
+ bool is_last)
+{
+ struct stm32f4_i2c_msg *f4_msg = &i2c_dev->msg;
+ void __iomem *reg = i2c_dev->base + STM32F4_I2C_CR1;
+ unsigned long timeout;
+ u32 mask;
+ int ret;
+
+ f4_msg->addr = i2c_8bit_addr_from_msg(msg);
+ f4_msg->buf = msg->buf;
+ f4_msg->count = msg->len;
+ f4_msg->result = 0;
+ f4_msg->stop = is_last;
+
+ reinit_completion(&i2c_dev->complete);
+
+ /* Enable events and errors interrupts */
+ mask = STM32F4_I2C_CR2_ITEVTEN | STM32F4_I2C_CR2_ITERREN;
+ stm32f4_i2c_set_bits(i2c_dev->base + STM32F4_I2C_CR2, mask);
+
+ if (is_first) {
+ ret = stm32f4_i2c_wait_free_bus(i2c_dev);
+ if (ret)
+ return ret;
+
+ /* START generation */
+ stm32f4_i2c_set_bits(reg, STM32F4_I2C_CR1_START);
+ }
+
+ timeout = wait_for_completion_timeout(&i2c_dev->complete,
+ i2c_dev->adap.timeout);
+ ret = f4_msg->result;
+
+ if (!timeout)
+ ret = -ETIMEDOUT;
+
+ return ret;
+}
+
+/**
+ * stm32f4_i2c_xfer() - Transfer combined I2C message
+ * @i2c_adap: Adapter pointer to the controller
+ * @msgs: Pointer to data to be written.
+ * @num: Number of messages to be executed
+ */
+static int stm32f4_i2c_xfer(struct i2c_adapter *i2c_adap, struct i2c_msg msgs[],
+ int num)
+{
+ struct stm32f4_i2c_dev *i2c_dev = i2c_get_adapdata(i2c_adap);
+ int ret, i;
+
+ ret = clk_enable(i2c_dev->clk);
+ if (ret) {
+ dev_err(i2c_dev->dev, "Failed to enable clock\n");
+ return ret;
+ }
+
+ for (i = 0; i < num && !ret; i++)
+ ret = stm32f4_i2c_xfer_msg(i2c_dev, &msgs[i], i == 0,
+ i == num - 1);
+
+ clk_disable(i2c_dev->clk);
+
+ return (ret < 0) ? ret : num;
+}
+
+static u32 stm32f4_i2c_func(struct i2c_adapter *adap)
+{
+ return I2C_FUNC_I2C | I2C_FUNC_SMBUS_EMUL;
+}
+
+static struct i2c_algorithm stm32f4_i2c_algo = {
+ .master_xfer = stm32f4_i2c_xfer,
+ .functionality = stm32f4_i2c_func,
+};
+
+static int stm32f4_i2c_probe(struct platform_device *pdev)
+{
+ struct device_node *np = pdev->dev.of_node;
+ struct stm32f4_i2c_dev *i2c_dev;
+ struct resource *res;
+ u32 irq_event, irq_error, clk_rate;
+ struct i2c_adapter *adap;
+ struct reset_control *rst;
+ int ret;
+
+ i2c_dev = devm_kzalloc(&pdev->dev, sizeof(*i2c_dev), GFP_KERNEL);
+ if (!i2c_dev)
+ return -ENOMEM;
+
+ res = platform_get_resource(pdev, IORESOURCE_MEM, 0);
+ i2c_dev->base = devm_ioremap_resource(&pdev->dev, res);
+ if (IS_ERR(i2c_dev->base))
+ return PTR_ERR(i2c_dev->base);
+
+ irq_event = irq_of_parse_and_map(np, 0);
+ if (!irq_event) {
+ dev_err(&pdev->dev, "IRQ event missing or invalid\n");
+ return -EINVAL;
+ }
+
+ irq_error = irq_of_parse_and_map(np, 1);
+ if (!irq_error) {
+ dev_err(&pdev->dev, "IRQ error missing or invalid\n");
+ return -EINVAL;
+ }
+
+ i2c_dev->clk = devm_clk_get(&pdev->dev, NULL);
+ if (IS_ERR(i2c_dev->clk)) {
+ dev_err(&pdev->dev, "Error: Missing controller clock\n");
+ return PTR_ERR(i2c_dev->clk);
+ }
+ ret = clk_prepare_enable(i2c_dev->clk);
+ if (ret) {
+ dev_err(i2c_dev->dev, "Failed to prepare_enable clock\n");
+ return ret;
+ }
+
+ rst = devm_reset_control_get(&pdev->dev, NULL);
+ if (IS_ERR(rst)) {
+ dev_err(&pdev->dev, "Error: Missing controller reset\n");
+ ret = PTR_ERR(rst);
+ goto clk_free;
+ }
+ reset_control_assert(rst);
+ udelay(2);
+ reset_control_deassert(rst);
+
+ i2c_dev->speed = STM32F4_I2C_SPEED_STANDARD;
+ ret = of_property_read_u32(np, "clock-frequency", &clk_rate);
+ if (!ret && clk_rate >= 400000)
+ i2c_dev->speed = STM32F4_I2C_SPEED_FAST;
+
+ i2c_dev->dev = &pdev->dev;
+
+ ret = devm_request_irq(&pdev->dev, irq_event, stm32f4_i2c_isr_event, 0,
+ pdev->name, i2c_dev);
+ if (ret) {
+ dev_err(&pdev->dev, "Failed to request irq event %i\n",
+ irq_event);
+ goto clk_free;
+ }
+
+ ret = devm_request_irq(&pdev->dev, irq_error, stm32f4_i2c_isr_error, 0,
+ pdev->name, i2c_dev);
+ if (ret) {
+ dev_err(&pdev->dev, "Failed to request irq error %i\n",
+ irq_error);
+ goto clk_free;
+ }
+
+ ret = stm32f4_i2c_hw_config(i2c_dev);
+ if (ret)
+ goto clk_free;
+
+ adap = &i2c_dev->adap;
+ i2c_set_adapdata(adap, i2c_dev);
+ snprintf(adap->name, sizeof(adap->name), "STM32 I2C(%pa)", &res->start);
+ adap->owner = THIS_MODULE;
+ adap->timeout = 2 * HZ;
+ adap->retries = 0;
+ adap->algo = &stm32f4_i2c_algo;
+ adap->dev.parent = &pdev->dev;
+ adap->dev.of_node = pdev->dev.of_node;
+
+ init_completion(&i2c_dev->complete);
+
+ ret = i2c_add_adapter(adap);
+ if (ret)
+ goto clk_free;
+
+ platform_set_drvdata(pdev, i2c_dev);
+
+ clk_disable(i2c_dev->clk);
+
+ dev_info(i2c_dev->dev, "STM32F4 I2C driver registered\n");
+
+ return 0;
+
+clk_free:
+ clk_disable_unprepare(i2c_dev->clk);
+ return ret;
+}
+
+static int stm32f4_i2c_remove(struct platform_device *pdev)
+{
+ struct stm32f4_i2c_dev *i2c_dev = platform_get_drvdata(pdev);
+
+ i2c_del_adapter(&i2c_dev->adap);
+
+ clk_unprepare(i2c_dev->clk);
+
+ return 0;
+}
+
+static const struct of_device_id stm32f4_i2c_match[] = {
+ { .compatible = "st,stm32f4-i2c", },
+ {},
+};
+MODULE_DEVICE_TABLE(of, stm32f4_i2c_match);
+
+static struct platform_driver stm32f4_i2c_driver = {
+ .driver = {
+ .name = "stm32f4-i2c",
+ .of_match_table = stm32f4_i2c_match,
+ },
+ .probe = stm32f4_i2c_probe,
+ .remove = stm32f4_i2c_remove,
+};
+
+module_platform_driver(stm32f4_i2c_driver);
+
+MODULE_AUTHOR("M'boumba Cedric Madianga <cedric.madianga@gmail.com>");
+MODULE_DESCRIPTION("STMicroelectronics STM32F4 I2C driver");
+MODULE_LICENSE("GPL v2");
diff --git a/drivers/i2c/busses/i2c-xgene-slimpro.c b/drivers/i2c/busses/i2c-xgene-slimpro.c
index 0ab1e55..dbe7e44 100644
--- a/drivers/i2c/busses/i2c-xgene-slimpro.c
+++ b/drivers/i2c/busses/i2c-xgene-slimpro.c
@@ -372,7 +372,7 @@ static u32 xgene_slimpro_i2c_func(struct i2c_adapter *adapter)
I2C_FUNC_SMBUS_I2C_BLOCK;
}
-static struct i2c_algorithm xgene_slimpro_i2c_algorithm = {
+static const struct i2c_algorithm xgene_slimpro_i2c_algorithm = {
.smbus_xfer = xgene_slimpro_i2c_xfer,
.functionality = xgene_slimpro_i2c_func,
};
diff --git a/drivers/i2c/busses/i2c-xlp9xx.c b/drivers/i2c/busses/i2c-xlp9xx.c
index 84a8b2e..66b464d 100644
--- a/drivers/i2c/busses/i2c-xlp9xx.c
+++ b/drivers/i2c/busses/i2c-xlp9xx.c
@@ -334,7 +334,7 @@ static u32 xlp9xx_i2c_functionality(struct i2c_adapter *adapter)
I2C_FUNC_10BIT_ADDR;
}
-static struct i2c_algorithm xlp9xx_i2c_algo = {
+static const struct i2c_algorithm xlp9xx_i2c_algo = {
.master_xfer = xlp9xx_i2c_xfer,
.functionality = xlp9xx_i2c_functionality,
};
diff --git a/drivers/i2c/busses/i2c-xlr.c b/drivers/i2c/busses/i2c-xlr.c
index ad17d88..484bfa15d 100644
--- a/drivers/i2c/busses/i2c-xlr.c
+++ b/drivers/i2c/busses/i2c-xlr.c
@@ -335,7 +335,7 @@ static u32 xlr_func(struct i2c_adapter *adap)
return (I2C_FUNC_SMBUS_EMUL & ~I2C_FUNC_SMBUS_QUICK) | I2C_FUNC_I2C;
}
-static struct i2c_algorithm xlr_i2c_algo = {
+static const struct i2c_algorithm xlr_i2c_algo = {
.master_xfer = xlr_i2c_xfer,
.functionality = xlr_func,
};
diff --git a/drivers/i2c/i2c-core.c b/drivers/i2c/i2c-core.c
index 583e950..408de74 100644
--- a/drivers/i2c/i2c-core.c
+++ b/drivers/i2c/i2c-core.c
@@ -3690,6 +3690,39 @@ int i2c_slave_unregister(struct i2c_client *client)
return ret;
}
EXPORT_SYMBOL_GPL(i2c_slave_unregister);
+
+/**
+ * i2c_detect_slave_mode - detect operation mode
+ * @dev: The device owning the bus
+ *
+ * This checks the device nodes for an I2C slave by checking the address
+ * used in the reg property. If the address match the I2C_OWN_SLAVE_ADDRESS
+ * flag this means the device is configured to act as a I2C slave and it will
+ * be listening at that address.
+ *
+ * Returns true if an I2C own slave address is detected, otherwise returns
+ * false.
+ */
+bool i2c_detect_slave_mode(struct device *dev)
+{
+ if (IS_BUILTIN(CONFIG_OF) && dev->of_node) {
+ struct device_node *child;
+ u32 reg;
+
+ for_each_child_of_node(dev->of_node, child) {
+ of_property_read_u32(child, "reg", ®);
+ if (reg & I2C_OWN_SLAVE_ADDRESS) {
+ of_node_put(child);
+ return true;
+ }
+ }
+ } else if (IS_BUILTIN(CONFIG_ACPI) && ACPI_HANDLE(dev)) {
+ dev_dbg(dev, "ACPI slave is not supported yet\n");
+ }
+ return false;
+}
+EXPORT_SYMBOL_GPL(i2c_detect_slave_mode);
+
#endif
MODULE_AUTHOR("Simon G. Vogl <simon@tk.uni-linz.ac.at>");
diff --git a/drivers/i2c/muxes/i2c-mux-mlxcpld.c b/drivers/i2c/muxes/i2c-mux-mlxcpld.c
index b7ca249..e53f2ab 100644
--- a/drivers/i2c/muxes/i2c-mux-mlxcpld.c
+++ b/drivers/i2c/muxes/i2c-mux-mlxcpld.c
@@ -40,7 +40,6 @@
#include <linux/module.h>
#include <linux/platform_device.h>
#include <linux/slab.h>
-#include <linux/version.h>
#include <linux/i2c/mlxcpld.h>
#define CPLD_MUX_MAX_NCHANS 8
diff --git a/drivers/i2c/muxes/i2c-mux-pca9541.c b/drivers/i2c/muxes/i2c-mux-pca9541.c
index 4ea7e69..77840f7 100644
--- a/drivers/i2c/muxes/i2c-mux-pca9541.c
+++ b/drivers/i2c/muxes/i2c-mux-pca9541.c
@@ -90,6 +90,7 @@ static const struct of_device_id pca9541_of_match[] = {
{ .compatible = "nxp,pca9541" },
{}
};
+MODULE_DEVICE_TABLE(of, pca9541_of_match);
#endif
/*
diff --git a/drivers/i2c/muxes/i2c-mux-pca954x.c b/drivers/i2c/muxes/i2c-mux-pca954x.c
index 06fd9cc..dfc1c0e 100644
--- a/drivers/i2c/muxes/i2c-mux-pca954x.c
+++ b/drivers/i2c/muxes/i2c-mux-pca954x.c
@@ -168,6 +168,7 @@ static const struct of_device_id pca954x_of_match[] = {
{ .compatible = "nxp,pca9548", .data = &chips[pca_9548] },
{}
};
+MODULE_DEVICE_TABLE(of, pca954x_of_match);
#endif
/* Write to mux register. Don't use i2c_transfer()/i2c_smbus_xfer()
diff --git a/include/linux/i2c.h b/include/linux/i2c.h
index 4b45ec4..f0ba4ba 100644
--- a/include/linux/i2c.h
+++ b/include/linux/i2c.h
@@ -282,6 +282,7 @@ enum i2c_slave_event {
extern int i2c_slave_register(struct i2c_client *client, i2c_slave_cb_t slave_cb);
extern int i2c_slave_unregister(struct i2c_client *client);
+extern bool i2c_detect_slave_mode(struct device *dev);
static inline int i2c_slave_event(struct i2c_client *client,
enum i2c_slave_event event, u8 *val)