diff options
Diffstat (limited to 'drivers/i2c')
| -rw-r--r-- | drivers/i2c/Kconfig | 7 | ||||
| -rw-r--r-- | drivers/i2c/Makefile | 1 | ||||
| -rw-r--r-- | drivers/i2c/i2c-cdns.c | 335 |
3 files changed, 343 insertions, 0 deletions
diff --git a/drivers/i2c/Kconfig b/drivers/i2c/Kconfig index 46b83e78941..9324c6c9e5f 100644 --- a/drivers/i2c/Kconfig +++ b/drivers/i2c/Kconfig @@ -58,6 +58,13 @@ config DM_I2C_GPIO bindings are supported. Binding info: doc/device-tree-bindings/i2c/i2c-gpio.txt +config SYS_I2C_CADENCE + tristate "Cadence I2C Controller" + depends on DM_I2C && (ARCH_ZYNQ || ARM64) + help + Say yes here to select Cadence I2C Host Controller. This controller is + e.g. used by Xilinx Zynq. + config SYS_I2C_INTEL bool "Intel I2C/SMBUS driver" depends on DM_I2C diff --git a/drivers/i2c/Makefile b/drivers/i2c/Makefile index c75c5793efe..167424db982 100644 --- a/drivers/i2c/Makefile +++ b/drivers/i2c/Makefile @@ -16,6 +16,7 @@ obj-$(CONFIG_PCA9564_I2C) += pca9564_i2c.o obj-$(CONFIG_TSI108_I2C) += tsi108_i2c.o obj-$(CONFIG_SH_SH7734_I2C) += sh_sh7734_i2c.o obj-$(CONFIG_SYS_I2C) += i2c_core.o +obj-$(CONFIG_SYS_I2C_CADENCE) += i2c-cdns.o obj-$(CONFIG_SYS_I2C_DAVINCI) += davinci_i2c.o obj-$(CONFIG_SYS_I2C_DW) += designware_i2c.o obj-$(CONFIG_SYS_I2C_FSL) += fsl_i2c.o diff --git a/drivers/i2c/i2c-cdns.c b/drivers/i2c/i2c-cdns.c new file mode 100644 index 00000000000..909cea24182 --- /dev/null +++ b/drivers/i2c/i2c-cdns.c @@ -0,0 +1,335 @@ +/* + * Copyright (C) 2015 Moritz Fischer <moritz.fischer@ettus.com> + * IP from Cadence (ID T-CS-PE-0007-100, Version R1p10f2) + * + * This file is based on: drivers/i2c/zynq_i2c.c, + * with added driver-model support and code cleanup. + * + * SPDX-License-Identifier: GPL-2.0+ + */ + +#include <common.h> +#include <linux/types.h> +#include <linux/io.h> +#include <asm/errno.h> +#include <dm/device.h> +#include <dm/root.h> +#include <i2c.h> +#include <fdtdec.h> +#include <mapmem.h> + +DECLARE_GLOBAL_DATA_PTR; + +/* i2c register set */ +struct cdns_i2c_regs { + u32 control; + u32 status; + u32 address; + u32 data; + u32 interrupt_status; + u32 transfer_size; + u32 slave_mon_pause; + u32 time_out; + u32 interrupt_mask; + u32 interrupt_enable; + u32 interrupt_disable; +}; + +/* Control register fields */ +#define CDNS_I2C_CONTROL_RW 0x00000001 +#define CDNS_I2C_CONTROL_MS 0x00000002 +#define CDNS_I2C_CONTROL_NEA 0x00000004 +#define CDNS_I2C_CONTROL_ACKEN 0x00000008 +#define CDNS_I2C_CONTROL_HOLD 0x00000010 +#define CDNS_I2C_CONTROL_SLVMON 0x00000020 +#define CDNS_I2C_CONTROL_CLR_FIFO 0x00000040 +#define CDNS_I2C_CONTROL_DIV_B_SHIFT 8 +#define CDNS_I2C_CONTROL_DIV_B_MASK 0x00003F00 +#define CDNS_I2C_CONTROL_DIV_A_SHIFT 14 +#define CDNS_I2C_CONTROL_DIV_A_MASK 0x0000C000 + +/* Status register values */ +#define CDNS_I2C_STATUS_RXDV 0x00000020 +#define CDNS_I2C_STATUS_TXDV 0x00000040 +#define CDNS_I2C_STATUS_RXOVF 0x00000080 +#define CDNS_I2C_STATUS_BA 0x00000100 + +/* Interrupt register fields */ +#define CDNS_I2C_INTERRUPT_COMP 0x00000001 +#define CDNS_I2C_INTERRUPT_DATA 0x00000002 +#define CDNS_I2C_INTERRUPT_NACK 0x00000004 +#define CDNS_I2C_INTERRUPT_TO 0x00000008 +#define CDNS_I2C_INTERRUPT_SLVRDY 0x00000010 +#define CDNS_I2C_INTERRUPT_RXOVF 0x00000020 +#define CDNS_I2C_INTERRUPT_TXOVF 0x00000040 +#define CDNS_I2C_INTERRUPT_RXUNF 0x00000080 +#define CDNS_I2C_INTERRUPT_ARBLOST 0x00000200 + +#define CDNS_I2C_FIFO_DEPTH 16 +#define CDNS_I2C_TRANSFER_SIZE_MAX 255 /* Controller transfer limit */ + +#ifdef DEBUG +static void cdns_i2c_debug_status(struct cdns_i2c_regs *cdns_i2c) +{ + int int_status; + int status; + int_status = readl(&cdns_i2c->interrupt_status); + + status = readl(&cdns_i2c->status); + if (int_status || status) { + debug("Status: "); + if (int_status & CDNS_I2C_INTERRUPT_COMP) + debug("COMP "); + if (int_status & CDNS_I2C_INTERRUPT_DATA) + debug("DATA "); + if (int_status & CDNS_I2C_INTERRUPT_NACK) + debug("NACK "); + if (int_status & CDNS_I2C_INTERRUPT_TO) + debug("TO "); + if (int_status & CDNS_I2C_INTERRUPT_SLVRDY) + debug("SLVRDY "); + if (int_status & CDNS_I2C_INTERRUPT_RXOVF) + debug("RXOVF "); + if (int_status & CDNS_I2C_INTERRUPT_TXOVF) + debug("TXOVF "); + if (int_status & CDNS_I2C_INTERRUPT_RXUNF) + debug("RXUNF "); + if (int_status & CDNS_I2C_INTERRUPT_ARBLOST) + debug("ARBLOST "); + if (status & CDNS_I2C_STATUS_RXDV) + debug("RXDV "); + if (status & CDNS_I2C_STATUS_TXDV) + debug("TXDV "); + if (status & CDNS_I2C_STATUS_RXOVF) + debug("RXOVF "); + if (status & CDNS_I2C_STATUS_BA) + debug("BA "); + debug("TS%d ", readl(&cdns_i2c->transfer_size)); + debug("\n"); + } +} +#endif + +struct i2c_cdns_bus { + int id; + struct cdns_i2c_regs __iomem *regs; /* register base */ +}; + + +/** cdns_i2c_probe() - Probe method + * @dev: udevice pointer + * + * DM callback called when device is probed + */ +static int cdns_i2c_probe(struct udevice *dev) +{ + struct i2c_cdns_bus *bus = dev_get_priv(dev); + + bus->regs = (struct cdns_i2c_regs *)dev_get_addr(dev); + if (!bus->regs) + return -ENOMEM; + + /* TODO: Calculate dividers based on CPU_CLK_1X */ + /* 111MHz / ( (3 * 17) * 22 ) = ~100KHz */ + writel((16 << CDNS_I2C_CONTROL_DIV_B_SHIFT) | + (2 << CDNS_I2C_CONTROL_DIV_A_SHIFT), &bus->regs->control); + + /* Enable master mode, ack, and 7-bit addressing */ + setbits_le32(&bus->regs->control, CDNS_I2C_CONTROL_MS | + CDNS_I2C_CONTROL_ACKEN | CDNS_I2C_CONTROL_NEA); + + debug("%s bus %d at %p\n", __func__, dev->seq, bus->regs); + + return 0; +} + +static int cdns_i2c_remove(struct udevice *dev) +{ + struct i2c_cdns_bus *bus = dev_get_priv(dev); + + debug("%s bus %d at %p\n", __func__, dev->seq, bus->regs); + + unmap_sysmem(bus->regs); + + return 0; +} + +/* Wait for an interrupt */ +static u32 cdns_i2c_wait(struct cdns_i2c_regs *cdns_i2c, u32 mask) +{ + int timeout, int_status; + + for (timeout = 0; timeout < 100; timeout++) { + udelay(100); + int_status = readl(&cdns_i2c->interrupt_status); + if (int_status & mask) + break; + } + + /* Clear interrupt status flags */ + writel(int_status & mask, &cdns_i2c->interrupt_status); + + return int_status & mask; +} + +static int cdns_i2c_set_bus_speed(struct udevice *dev, unsigned int speed) +{ + if (speed != 100000) { + printf("%s, failed to set clock speed to %u\n", __func__, + speed); + return -EINVAL; + } + + return 0; +} + +/* Probe to see if a chip is present. */ +static int cdns_i2c_probe_chip(struct udevice *bus, uint chip_addr, + uint chip_flags) +{ + struct i2c_cdns_bus *i2c_bus = dev_get_priv(bus); + struct cdns_i2c_regs *regs = i2c_bus->regs; + + /* Attempt to read a byte */ + setbits_le32(®s->control, CDNS_I2C_CONTROL_CLR_FIFO | + CDNS_I2C_CONTROL_RW); + clrbits_le32(®s->control, CDNS_I2C_CONTROL_HOLD); + writel(0xFF, ®s->interrupt_status); + writel(chip_addr, ®s->address); + writel(1, ®s->transfer_size); + + return (cdns_i2c_wait(regs, CDNS_I2C_INTERRUPT_COMP | + CDNS_I2C_INTERRUPT_NACK) & + CDNS_I2C_INTERRUPT_COMP) ? 0 : -ETIMEDOUT; +} + +static int cdns_i2c_write_data(struct i2c_cdns_bus *i2c_bus, u32 addr, u8 *data, + u32 len, bool next_is_read) +{ + u8 *cur_data = data; + + struct cdns_i2c_regs *regs = i2c_bus->regs; + + setbits_le32(®s->control, CDNS_I2C_CONTROL_CLR_FIFO | + CDNS_I2C_CONTROL_HOLD); + + /* if next is a read, we need to clear HOLD, doesn't work */ + if (next_is_read) + clrbits_le32(®s->control, CDNS_I2C_CONTROL_HOLD); + + clrbits_le32(®s->control, CDNS_I2C_CONTROL_RW); + + writel(0xFF, ®s->interrupt_status); + writel(addr, ®s->address); + + while (len--) { + writel(*(cur_data++), ®s->data); + if (readl(®s->transfer_size) == CDNS_I2C_FIFO_DEPTH) { + if (!cdns_i2c_wait(regs, CDNS_I2C_INTERRUPT_COMP)) { + /* Release the bus */ + clrbits_le32(®s->control, + CDNS_I2C_CONTROL_HOLD); + return -ETIMEDOUT; + } + } + } + + /* All done... release the bus */ + clrbits_le32(®s->control, CDNS_I2C_CONTROL_HOLD); + /* Wait for the address and data to be sent */ + if (!cdns_i2c_wait(regs, CDNS_I2C_INTERRUPT_COMP)) + return -ETIMEDOUT; + return 0; +} + +static int cdns_i2c_read_data(struct i2c_cdns_bus *i2c_bus, u32 addr, u8 *data, + u32 len) +{ + u32 status; + u32 i = 0; + u8 *cur_data = data; + + /* TODO: Fix this */ + struct cdns_i2c_regs *regs = i2c_bus->regs; + + /* Check the hardware can handle the requested bytes */ + if ((len < 0) || (len > CDNS_I2C_TRANSFER_SIZE_MAX)) + return -EINVAL; + + setbits_le32(®s->control, CDNS_I2C_CONTROL_CLR_FIFO | + CDNS_I2C_CONTROL_RW); + + /* Start reading data */ + writel(addr, ®s->address); + writel(len, ®s->transfer_size); + + /* Wait for data */ + do { + status = cdns_i2c_wait(regs, CDNS_I2C_INTERRUPT_COMP | + CDNS_I2C_INTERRUPT_DATA); + if (!status) { + /* Release the bus */ + clrbits_le32(®s->control, CDNS_I2C_CONTROL_HOLD); + return -ETIMEDOUT; + } + debug("Read %d bytes\n", + len - readl(®s->transfer_size)); + for (; i < len - readl(®s->transfer_size); i++) + *(cur_data++) = readl(®s->data); + } while (readl(®s->transfer_size) != 0); + /* All done... release the bus */ + clrbits_le32(®s->control, CDNS_I2C_CONTROL_HOLD); + +#ifdef DEBUG + cdns_i2c_debug_status(regs); +#endif + return 0; +} + +static int cdns_i2c_xfer(struct udevice *dev, struct i2c_msg *msg, + int nmsgs) +{ + struct i2c_cdns_bus *i2c_bus = dev_get_priv(dev); + int ret; + + debug("i2c_xfer: %d messages\n", nmsgs); + for (; nmsgs > 0; nmsgs--, msg++) { + bool next_is_read = nmsgs > 1 && (msg[1].flags & I2C_M_RD); + + debug("i2c_xfer: chip=0x%x, len=0x%x\n", msg->addr, msg->len); + if (msg->flags & I2C_M_RD) { + ret = cdns_i2c_read_data(i2c_bus, msg->addr, msg->buf, + msg->len); + } else { + ret = cdns_i2c_write_data(i2c_bus, msg->addr, msg->buf, + msg->len, next_is_read); + } + if (ret) { + debug("i2c_write: error sending\n"); + return -EREMOTEIO; + } + } + + return 0; +} + +static const struct dm_i2c_ops cdns_i2c_ops = { + .xfer = cdns_i2c_xfer, + .probe_chip = cdns_i2c_probe_chip, + .set_bus_speed = cdns_i2c_set_bus_speed, +}; + +static const struct udevice_id cdns_i2c_of_match[] = { + { .compatible = "cdns,i2c-r1p10" }, + { /* end of table */ } +}; + +U_BOOT_DRIVER(cdns_i2c) = { + .name = "i2c-cdns", + .id = UCLASS_I2C, + .of_match = cdns_i2c_of_match, + .probe = cdns_i2c_probe, + .remove = cdns_i2c_remove, + .priv_auto_alloc_size = sizeof(struct i2c_cdns_bus), + .ops = &cdns_i2c_ops, +}; |