Signed-off-by: Michael Burr michael.burr@logicpd.com Cc: Heiko Schocher hs@denx.de Cc: Michal Simek monstr@monstr.eu --- === Note: this patch depends on the previous patch titled === "[PATCH] I2C: Zynq: Support for 0-length register address" === submitted 24 Sep. 2013.
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.
drivers/i2c/zynq_i2c.c | 108 ++++++++++++++++++++++++++++++------------------ 1 file changed, 67 insertions(+), 41 deletions(-)
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)