[U-Boot] [PATCH v4 0/2] I2C: Zynq
This series of two patches contains improvements for the I2C driver on the Xilinx Zynq architecture. In general, the goals are:
Support for both I2C bus masters ("I2C0" and "I2C1") in the Zynq PS. Full support for bus multiplexers. Support for all register-address sizes (0, 1, 2).
The changes to file 'zynq_i2c.c' in this patch series are meant to be applied in order: in other words, first apply the changes from the PATCH 1/2 version; then apply the changes in the PATCH 2/2 version.
v3: fixed mistake parsing PATCH 1/2 v4: _really_ fixed this time!
Michael Burr (2): I2C: Zynq: Support for 0-length register address I2C:Zynq: Adapt this driver to the new model
README | 9 +++ drivers/i2c/Makefile | 2 +- drivers/i2c/zynq_i2c.c | 147 +++++++++++++++++++++++++++++------------------- include/configs/zynq.h | 10 ++-- 4 files changed, 102 insertions(+), 66 deletions(-)
Fixed bug with alen == 0 in 'i2c_write', 'i2c_read'
Further minor corrections:
Write 'address' register before 'data' register. Write 'transfer_size' register before 'address' register.
Signed-off-by: Michael Burr michael.burr@logicpd.com Cc: Heiko Schocher hs@denx.de Cc: Michal Simek monstr@monstr.eu
--- Tested: Xilinx ZC702 eval board. Write and read registers with addresses of length 0 and 1.
Change history: v2: put this in a series instead of by itself v3: fixed formatting problem in patch message v4: _really_ fixed this time!
--- drivers/i2c/zynq_i2c.c | 43 +++++++++++++++++++++++-------------------- 1 file changed, 23 insertions(+), 20 deletions(-)
diff --git a/drivers/i2c/zynq_i2c.c b/drivers/i2c/zynq_i2c.c index ce2d23f..9cbd3e4 100644 --- a/drivers/i2c/zynq_i2c.c +++ b/drivers/i2c/zynq_i2c.c @@ -187,20 +187,22 @@ int i2c_read(u8 dev, uint addr, int alen, u8 *data, int length) * Temporarily disable restart (by clearing hold) * It doesn't seem to work. */ - clrbits_le32(&zynq_i2c->control, ZYNQ_I2C_CONTROL_RW | - ZYNQ_I2C_CONTROL_HOLD); + clrbits_le32(&zynq_i2c->control, ZYNQ_I2C_CONTROL_HOLD); writel(0xFF, &zynq_i2c->interrupt_status); - while (alen--) - writel(addr >> (8*alen), &zynq_i2c->data); - writel(dev, &zynq_i2c->address); + if (alen) { + clrbits_le32(&zynq_i2c->control, ZYNQ_I2C_CONTROL_RW); + writel(dev, &zynq_i2c->address); + while (alen--) + writel(addr >> (8*alen), &zynq_i2c->data);
- /* Wait for the address to be sent */ - if (!zynq_i2c_wait(ZYNQ_I2C_INTERRUPT_COMP)) { - /* Release the bus */ - clrbits_le32(&zynq_i2c->control, ZYNQ_I2C_CONTROL_HOLD); - return -ETIMEDOUT; + /* Wait for the address to be sent */ + if (!zynq_i2c_wait(ZYNQ_I2C_INTERRUPT_COMP)) { + /* Release the bus */ + clrbits_le32(&zynq_i2c->control, ZYNQ_I2C_CONTROL_HOLD); + return -ETIMEDOUT; + } + debug("Device acked address\n"); } - debug("Device acked address\n");
setbits_le32(&zynq_i2c->control, ZYNQ_I2C_CONTROL_CLR_FIFO | ZYNQ_I2C_CONTROL_RW); @@ -244,17 +246,18 @@ int i2c_write(u8 dev, uint addr, int alen, u8 *data, int length) ZYNQ_I2C_CONTROL_HOLD); clrbits_le32(&zynq_i2c->control, ZYNQ_I2C_CONTROL_RW); writel(0xFF, &zynq_i2c->interrupt_status); - while (alen--) - writel(addr >> (8*alen), &zynq_i2c->data); - /* Start the tranfer */ writel(dev, &zynq_i2c->address); - if (!zynq_i2c_wait(ZYNQ_I2C_INTERRUPT_COMP)) { - /* Release the bus */ - clrbits_le32(&zynq_i2c->control, ZYNQ_I2C_CONTROL_HOLD); - return -ETIMEDOUT; + if (alen) { + while (alen--) + writel(addr >> (8*alen), &zynq_i2c->data); + /* Start the tranfer */ + if (!zynq_i2c_wait(ZYNQ_I2C_INTERRUPT_COMP)) { + /* Release the bus */ + clrbits_le32(&zynq_i2c->control, ZYNQ_I2C_CONTROL_HOLD); + return -ETIMEDOUT; + } + debug("Device acked address\n"); } - - debug("Device acked address\n"); while (length--) { writel(*(cur_data++), &zynq_i2c->data); if (readl(&zynq_i2c->transfer_size) == ZYNQ_I2C_FIFO_DEPTH) {
Driver 'zynq_i2c.c' together with CONFIGs, README, and Makefile.
Signed-off-by: Michael Burr michael.burr@logicpd.com Cc: Heiko Schocher hs@denx.de Cc: Michal Simek monstr@monstr.eu
--- Note: the changes to file 'zynq_i2c.c' in this patch series are meant to be applied in order: in other words, first apply the changes from the 1/2 version; then apply the changes in the 2/2 version.
Tested on Xilinx ZC702 eval board: Select various I2C chips using TI PCA9548 bus multiplexer. Write and read registers with addresses of length 0 and 1.
--- README | 9 ++++ drivers/i2c/Makefile | 2 +- drivers/i2c/zynq_i2c.c | 108 ++++++++++++++++++++++++++++++------------------ include/configs/zynq.h | 10 ++--- 4 files changed, 81 insertions(+), 48 deletions(-)
diff --git a/README b/README index ccd47fa..fd2c8fc 100644 --- a/README +++ b/README @@ -1995,6 +1995,15 @@ CBFS (Coreboot Filesystem) support - CONFIG_SYS_I2C_PPC4XX_CH0 activate hardware channel 0 - CONFIG_SYS_I2C_PPC4XX_CH1 activate hardware channel 1
+ - drivers/i2c/zynq_i2c.c + - Activate this driver with CONFIG_SYS_I2C_ZYNQ + - This driver operates only as bus-master (i.e. slave- + address == 0) and supports only 100 kbps speed. + - Both bus-controller devices in the Zynq PS (I2C0 and I2C1) + are supported. (However, note that Zynq PL configuration + may be needed in order to route some bus lines to external + pins.) + additional defines:
CONFIG_SYS_NUM_I2C_BUSES diff --git a/drivers/i2c/Makefile b/drivers/i2c/Makefile index 37ccbd1..55ce32d 100644 --- a/drivers/i2c/Makefile +++ b/drivers/i2c/Makefile @@ -32,7 +32,7 @@ COBJS-$(CONFIG_SYS_I2C_FTI2C010) += fti2c010.o COBJS-$(CONFIG_SYS_I2C_PPC4XX) += ppc4xx_i2c.o COBJS-$(CONFIG_SYS_I2C_SOFT) += soft_i2c.o COBJS-$(CONFIG_SYS_I2C_TEGRA) += tegra_i2c.o -COBJS-$(CONFIG_ZYNQ_I2C) += zynq_i2c.o +COBJS-$(CONFIG_SYS_I2C_ZYNQ) += zynq_i2c.o
COBJS := $(COBJS-y) SRCS := $(COBJS:.o=.c) diff --git a/drivers/i2c/zynq_i2c.c b/drivers/i2c/zynq_i2c.c index 9cbd3e4..7972a59 100644 --- a/drivers/i2c/zynq_i2c.c +++ b/drivers/i2c/zynq_i2c.c @@ -7,6 +7,8 @@ * * Copyright (c) 2012-2013 Xilinx, Michal Simek * + * Copyright (c) 2013 Logic PD, Michael Burr + * * SPDX-License-Identifier: GPL-2.0+ */
@@ -64,18 +66,28 @@ struct zynq_i2c_registers { #define ZYNQ_I2C_FIFO_DEPTH 16 #define ZYNQ_I2C_TRANSFERT_SIZE_MAX 255 /* Controller transfer limit */
-#if defined(CONFIG_ZYNQ_I2C0) -# define ZYNQ_I2C_BASE ZYNQ_I2C_BASEADDR0 -#else -# define ZYNQ_I2C_BASE ZYNQ_I2C_BASEADDR1 -#endif - -static struct zynq_i2c_registers *zynq_i2c = - (struct zynq_i2c_registers *)ZYNQ_I2C_BASE; +static struct zynq_i2c_registers *i2c_select(struct i2c_adapter *adap) +{ + return adap->hwadapnr ? + /* Zynq PS I2C1 */ + (struct zynq_i2c_registers *)ZYNQ_I2C_BASEADDR1 : + /* Zynq PS I2C0 */ + (struct zynq_i2c_registers *)ZYNQ_I2C_BASEADDR0; +}
/* I2C init called by cmd_i2c when doing 'i2c reset'. */ -void i2c_init(int requested_speed, int slaveadd) +static void zynq_i2c_init(struct i2c_adapter *adap, int speed, int slaveaddr) { + struct zynq_i2c_registers *zynq_i2c = i2c_select(adap); + + if (speed != 100000) + debug("Warning: requested speed not supported.\n"); + if (slaveaddr) + debug("Warning: slave mode not supported.\n"); + + /* The following _assumes_ clock rate cpu_1x = 111 MHz */ + /* This could use improvement! Also see 'i2c_set_bus_speed' below */ + /* 111MHz / ( (3 * 17) * 22 ) = ~100KHz */ writel((16 << ZYNQ_I2C_CONTROL_DIV_B_SHIFT) | (2 << ZYNQ_I2C_CONTROL_DIV_A_SHIFT), &zynq_i2c->control); @@ -86,7 +98,7 @@ void i2c_init(int requested_speed, int slaveadd) }
#ifdef DEBUG -static void zynq_i2c_debug_status(void) +static void zynq_i2c_debug_status(struct zynq_i2c_registers *zynq_i2c) { int int_status; int status; @@ -128,7 +140,7 @@ static void zynq_i2c_debug_status(void) #endif
/* Wait for an interrupt */ -static u32 zynq_i2c_wait(u32 mask) +static u32 zynq_i2c_wait(struct zynq_i2c_registers *zynq_i2c, u32 mask) { int timeout, int_status;
@@ -139,7 +151,7 @@ static u32 zynq_i2c_wait(u32 mask) break; } #ifdef DEBUG - zynq_i2c_debug_status(); + zynq_i2c_debug_status(zynq_i2c); #endif /* Clear interrupt status flags */ writel(int_status & mask, &zynq_i2c->interrupt_status); @@ -151,17 +163,19 @@ static u32 zynq_i2c_wait(u32 mask) * I2C probe called by cmd_i2c when doing 'i2c probe'. * Begin read, nak data byte, end. */ -int i2c_probe(u8 dev) +static int zynq_i2c_probe(struct i2c_adapter *adap, uint8_t chip) { + struct zynq_i2c_registers *zynq_i2c = i2c_select(adap); + /* Attempt to read a byte */ setbits_le32(&zynq_i2c->control, ZYNQ_I2C_CONTROL_CLR_FIFO | ZYNQ_I2C_CONTROL_RW); clrbits_le32(&zynq_i2c->control, ZYNQ_I2C_CONTROL_HOLD); writel(0xFF, &zynq_i2c->interrupt_status); - writel(dev, &zynq_i2c->address); + writel(chip, &zynq_i2c->address); writel(1, &zynq_i2c->transfer_size);
- return (zynq_i2c_wait(ZYNQ_I2C_INTERRUPT_COMP | + return (zynq_i2c_wait(zynq_i2c, ZYNQ_I2C_INTERRUPT_COMP | ZYNQ_I2C_INTERRUPT_NACK) & ZYNQ_I2C_INTERRUPT_COMP) ? 0 : -ETIMEDOUT; } @@ -170,14 +184,18 @@ int i2c_probe(u8 dev) * I2C read called by cmd_i2c when doing 'i2c read' and by cmd_eeprom.c * Begin write, send address byte(s), begin read, receive data bytes, end. */ -int i2c_read(u8 dev, uint addr, int alen, u8 *data, int length) +static int zynq_i2c_read(struct i2c_adapter *adap, uint8_t chip, uint addr, + int alen, uint8_t *buffer, int len) { + struct zynq_i2c_registers *zynq_i2c; u32 status; u32 i = 0; - u8 *cur_data = data; + u8 *cur_data = buffer; + + zynq_i2c = i2c_select(adap);
/* Check the hardware can handle the requested bytes */ - if ((length < 0) || (length > ZYNQ_I2C_TRANSFERT_SIZE_MAX)) + if ((len < 0) || (len > ZYNQ_I2C_TRANSFERT_SIZE_MAX)) return -EINVAL;
/* Write the register address */ @@ -191,12 +209,12 @@ int i2c_read(u8 dev, uint addr, int alen, u8 *data, int length) writel(0xFF, &zynq_i2c->interrupt_status); if (alen) { clrbits_le32(&zynq_i2c->control, ZYNQ_I2C_CONTROL_RW); - writel(dev, &zynq_i2c->address); + writel(chip, &zynq_i2c->address); while (alen--) writel(addr >> (8*alen), &zynq_i2c->data);
/* Wait for the address to be sent */ - if (!zynq_i2c_wait(ZYNQ_I2C_INTERRUPT_COMP)) { + if (!zynq_i2c_wait(zynq_i2c, ZYNQ_I2C_INTERRUPT_COMP)) { /* Release the bus */ clrbits_le32(&zynq_i2c->control, ZYNQ_I2C_CONTROL_HOLD); return -ETIMEDOUT; @@ -207,12 +225,12 @@ int i2c_read(u8 dev, uint addr, int alen, u8 *data, int length) setbits_le32(&zynq_i2c->control, ZYNQ_I2C_CONTROL_CLR_FIFO | ZYNQ_I2C_CONTROL_RW); /* Start reading data */ - writel(dev, &zynq_i2c->address); - writel(length, &zynq_i2c->transfer_size); + writel(len, &zynq_i2c->transfer_size); + writel(chip, &zynq_i2c->address);
/* Wait for data */ do { - status = zynq_i2c_wait(ZYNQ_I2C_INTERRUPT_COMP | + status = zynq_i2c_wait(zynq_i2c, ZYNQ_I2C_INTERRUPT_COMP | ZYNQ_I2C_INTERRUPT_DATA); if (!status) { /* Release the bus */ @@ -220,15 +238,15 @@ int i2c_read(u8 dev, uint addr, int alen, u8 *data, int length) return -ETIMEDOUT; } debug("Read %d bytes\n", - length - readl(&zynq_i2c->transfer_size)); - for (; i < length - readl(&zynq_i2c->transfer_size); i++) + len - readl(&zynq_i2c->transfer_size)); + for (; i < len - readl(&zynq_i2c->transfer_size); i++) *(cur_data++) = readl(&zynq_i2c->data); } while (readl(&zynq_i2c->transfer_size) != 0); /* All done... release the bus */ clrbits_le32(&zynq_i2c->control, ZYNQ_I2C_CONTROL_HOLD);
#ifdef DEBUG - zynq_i2c_debug_status(); + zynq_i2c_debug_status(zynq_i2c); #endif return 0; } @@ -237,31 +255,35 @@ int i2c_read(u8 dev, uint addr, int alen, u8 *data, int length) * I2C write called by cmd_i2c when doing 'i2c write' and by cmd_eeprom.c * Begin write, send address byte(s), send data bytes, end. */ -int i2c_write(u8 dev, uint addr, int alen, u8 *data, int length) +static int zynq_i2c_write(struct i2c_adapter *adap, uint8_t chip, uint addr, + int alen, uint8_t *buffer, int len) { - u8 *cur_data = data; + struct zynq_i2c_registers *zynq_i2c; + u8 *cur_data = buffer; + + zynq_i2c = i2c_select(adap);
/* Write the register address */ setbits_le32(&zynq_i2c->control, ZYNQ_I2C_CONTROL_CLR_FIFO | ZYNQ_I2C_CONTROL_HOLD); clrbits_le32(&zynq_i2c->control, ZYNQ_I2C_CONTROL_RW); writel(0xFF, &zynq_i2c->interrupt_status); - writel(dev, &zynq_i2c->address); + writel(chip, &zynq_i2c->address); if (alen) { while (alen--) writel(addr >> (8*alen), &zynq_i2c->data); /* Start the tranfer */ - if (!zynq_i2c_wait(ZYNQ_I2C_INTERRUPT_COMP)) { + if (!zynq_i2c_wait(zynq_i2c, ZYNQ_I2C_INTERRUPT_COMP)) { /* Release the bus */ clrbits_le32(&zynq_i2c->control, ZYNQ_I2C_CONTROL_HOLD); return -ETIMEDOUT; } debug("Device acked address\n"); } - while (length--) { + while (len--) { writel(*(cur_data++), &zynq_i2c->data); if (readl(&zynq_i2c->transfer_size) == ZYNQ_I2C_FIFO_DEPTH) { - if (!zynq_i2c_wait(ZYNQ_I2C_INTERRUPT_COMP)) { + if (!zynq_i2c_wait(zynq_i2c, ZYNQ_I2C_INTERRUPT_COMP)) { /* Release the bus */ clrbits_le32(&zynq_i2c->control, ZYNQ_I2C_CONTROL_HOLD); @@ -273,21 +295,25 @@ int i2c_write(u8 dev, uint addr, int alen, u8 *data, int length) /* All done... release the bus */ clrbits_le32(&zynq_i2c->control, ZYNQ_I2C_CONTROL_HOLD); /* Wait for the address and data to be sent */ - if (!zynq_i2c_wait(ZYNQ_I2C_INTERRUPT_COMP)) + if (!zynq_i2c_wait(zynq_i2c, ZYNQ_I2C_INTERRUPT_COMP)) return -ETIMEDOUT; return 0; }
-int i2c_set_bus_num(unsigned int bus) +static uint zynq_i2c_set_bus_speed(struct i2c_adapter *adap, uint speed) { - /* Only support bus 0 */ - if (bus > 0) + /* struct zynq_i2c_registers *zynq_i2c = i2c_select(adap); */ + + /* Bus-speed selection is not implemented */ + if (speed != 100000) return -1; - return 0; -}
-unsigned int i2c_get_bus_num(void) -{ - /* Only support bus 0 */ return 0; } + +U_BOOT_I2C_ADAP_COMPLETE(ZYNQ_I2C0, zynq_i2c_init, zynq_i2c_probe, + zynq_i2c_read, zynq_i2c_write, + zynq_i2c_set_bus_speed, 100000, 0, 0) +U_BOOT_I2C_ADAP_COMPLETE(ZYNQ_I2C1, zynq_i2c_init, zynq_i2c_probe, + zynq_i2c_read, zynq_i2c_write, + zynq_i2c_set_bus_speed, 100000, 0, 1) diff --git a/include/configs/zynq.h b/include/configs/zynq.h index b9f381f..1ae915f 100644 --- a/include/configs/zynq.h +++ b/include/configs/zynq.h @@ -56,15 +56,13 @@ # define CONFIG_DOS_PARTITION #endif
-#define CONFIG_ZYNQ_I2C0 - /* I2C */ -#if defined(CONFIG_ZYNQ_I2C0) || defined(CONFIG_ZYNQ_I2C1) +#define CONFIG_SYS_I2C_ZYNQ +#ifdef CONFIG_SYS_I2C_ZYNQ +# define CONFIG_SYS_I2C # define CONFIG_CMD_I2C -# define CONFIG_ZYNQ_I2C -# define CONFIG_HARD_I2C # define CONFIG_SYS_I2C_SPEED 100000 -# define CONFIG_SYS_I2C_SLAVE 1 +# define CONFIG_SYS_I2C_SLAVE 0 #endif
#if defined(CONFIG_ZYNQ_DCC)
participants (1)
-
Michael Burr