diff options
Diffstat (limited to 'drivers/i2c')
| -rw-r--r-- | drivers/i2c/Makefile | 1 | ||||
| -rw-r--r-- | drivers/i2c/tegra_i2c.c | 569 |
2 files changed, 570 insertions, 0 deletions
diff --git a/drivers/i2c/Makefile b/drivers/i2c/Makefile index 504db03..f86e46c 100644 --- a/drivers/i2c/Makefile +++ b/drivers/i2c/Makefile @@ -41,6 +41,7 @@ COBJS-$(CONFIG_DRIVER_S3C24X0_I2C) += s3c24x0_i2c.o COBJS-$(CONFIG_S3C44B0_I2C) += s3c44b0_i2c.o COBJS-$(CONFIG_SOFT_I2C) += soft_i2c.o COBJS-$(CONFIG_SPEAR_I2C) += spr_i2c.o +COBJS-$(CONFIG_TEGRA_I2C) += tegra_i2c.o COBJS-$(CONFIG_TSI108_I2C) += tsi108_i2c.o COBJS-$(CONFIG_U8500_I2C) += u8500_i2c.o COBJS-$(CONFIG_SH_I2C) += sh_i2c.o diff --git a/drivers/i2c/tegra_i2c.c b/drivers/i2c/tegra_i2c.c new file mode 100644 index 0000000..21f6897 --- /dev/null +++ b/drivers/i2c/tegra_i2c.c @@ -0,0 +1,569 @@ +/* + * Copyright (c) 2012 The Chromium OS Authors. All rights reserved. + * Copyright (c) 2010-2011 NVIDIA Corporation + * NVIDIA Corporation <www.nvidia.com> + * + * See file CREDITS for list of people who contributed to this + * project. + * + * This program is free software; you can redistribute it and/or + * modify it under the terms of the GNU General Public License as + * published by the Free Software Foundation; either version 2 of + * the License, or (at your option) any later version. + * + * This program is distributed in the hope that it will be useful, + * but WITHOUT ANY WARRANTY; without even the implied warranty of + * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the + * GNU General Public License for more details. + * + * You should have received a copy of the GNU General Public License + * along with this program; if not, write to the Free Software + * Foundation, Inc., 59 Temple Place, Suite 330, Boston, + * MA 02111-1307 USA + */ + +#include <common.h> +#include <fdtdec.h> +#include <i2c.h> +#include <asm/io.h> +#include <asm/arch/clk_rst.h> +#include <asm/arch/clock.h> +#include <asm/arch/funcmux.h> +#include <asm/arch/gpio.h> +#include <asm/arch/pinmux.h> +#include <asm/arch/tegra_i2c.h> + +DECLARE_GLOBAL_DATA_PTR; + +static unsigned int i2c_bus_num; + +/* Information about i2c controller */ +struct i2c_bus { + int id; + enum periph_id periph_id; + int speed; + int pinmux_config; + struct i2c_control *control; + struct i2c_ctlr *regs; + int is_dvc; /* DVC type, rather than I2C */ + int inited; /* bus is inited */ +}; + +static struct i2c_bus i2c_controllers[TEGRA_I2C_NUM_CONTROLLERS]; + +static void set_packet_mode(struct i2c_bus *i2c_bus) +{ + u32 config; + + config = I2C_CNFG_NEW_MASTER_FSM_MASK | I2C_CNFG_PACKET_MODE_MASK; + + if (i2c_bus->is_dvc) { + struct dvc_ctlr *dvc = (struct dvc_ctlr *)i2c_bus->regs; + + writel(config, &dvc->cnfg); + } else { + writel(config, &i2c_bus->regs->cnfg); + /* + * program I2C_SL_CNFG.NEWSL to ENABLE. This fixes probe + * issues, i.e., some slaves may be wrongly detected. + */ + setbits_le32(&i2c_bus->regs->sl_cnfg, I2C_SL_CNFG_NEWSL_MASK); + } +} + +static void i2c_reset_controller(struct i2c_bus *i2c_bus) +{ + /* Reset I2C controller. */ + reset_periph(i2c_bus->periph_id, 1); + + /* re-program config register to packet mode */ + set_packet_mode(i2c_bus); +} + +static void i2c_init_controller(struct i2c_bus *i2c_bus) +{ + /* + * Use PLLP - DP-04508-001_v06 datasheet indicates a divisor of 8 + * here, in section 23.3.1, but in fact we seem to need a factor of + * 16 to get the right frequency. + */ + clock_start_periph_pll(i2c_bus->periph_id, CLOCK_ID_PERIPH, + i2c_bus->speed * 2 * 8); + + /* Reset I2C controller. */ + i2c_reset_controller(i2c_bus); + + /* Configure I2C controller. */ + if (i2c_bus->is_dvc) { /* only for DVC I2C */ + struct dvc_ctlr *dvc = (struct dvc_ctlr *)i2c_bus->regs; + + setbits_le32(&dvc->ctrl3, DVC_CTRL_REG3_I2C_HW_SW_PROG_MASK); + } + + funcmux_select(i2c_bus->periph_id, i2c_bus->pinmux_config); +} + +static void send_packet_headers( + struct i2c_bus *i2c_bus, + struct i2c_trans_info *trans, + u32 packet_id) +{ + u32 data; + + /* prepare header1: Header size = 0 Protocol = I2C, pktType = 0 */ + data = PROTOCOL_TYPE_I2C << PKT_HDR1_PROTOCOL_SHIFT; + data |= packet_id << PKT_HDR1_PKT_ID_SHIFT; + data |= i2c_bus->id << PKT_HDR1_CTLR_ID_SHIFT; + writel(data, &i2c_bus->control->tx_fifo); + debug("pkt header 1 sent (0x%x)\n", data); + + /* prepare header2 */ + data = (trans->num_bytes - 1) << PKT_HDR2_PAYLOAD_SIZE_SHIFT; + writel(data, &i2c_bus->control->tx_fifo); + debug("pkt header 2 sent (0x%x)\n", data); + + /* prepare IO specific header: configure the slave address */ + data = trans->address << PKT_HDR3_SLAVE_ADDR_SHIFT; + + /* Enable Read if it is not a write transaction */ + if (!(trans->flags & I2C_IS_WRITE)) + data |= PKT_HDR3_READ_MODE_MASK; + + /* Write I2C specific header */ + writel(data, &i2c_bus->control->tx_fifo); + debug("pkt header 3 sent (0x%x)\n", data); +} + +static int wait_for_tx_fifo_empty(struct i2c_control *control) +{ + u32 count; + int timeout_us = I2C_TIMEOUT_USEC; + + while (timeout_us >= 0) { + count = (readl(&control->fifo_status) & TX_FIFO_EMPTY_CNT_MASK) + >> TX_FIFO_EMPTY_CNT_SHIFT; + if (count == I2C_FIFO_DEPTH) + return 1; + udelay(10); + timeout_us -= 10; + } + + return 0; +} + +static int wait_for_rx_fifo_notempty(struct i2c_control *control) +{ + u32 count; + int timeout_us = I2C_TIMEOUT_USEC; + + while (timeout_us >= 0) { + count = (readl(&control->fifo_status) & TX_FIFO_FULL_CNT_MASK) + >> TX_FIFO_FULL_CNT_SHIFT; + if (count) + return 1; + udelay(10); + timeout_us -= 10; + } + + return 0; +} + +static int wait_for_transfer_complete(struct i2c_control *control) +{ + int int_status; + int timeout_us = I2C_TIMEOUT_USEC; + + while (timeout_us >= 0) { + int_status = readl(&control->int_status); + if (int_status & I2C_INT_NO_ACK_MASK) + return -int_status; + if (int_status & I2C_INT_ARBITRATION_LOST_MASK) + return -int_status; + if (int_status & I2C_INT_XFER_COMPLETE_MASK) + return 0; + + udelay(10); + timeout_us -= 10; + } + + return -1; +} + +static int send_recv_packets(struct i2c_bus *i2c_bus, + struct i2c_trans_info *trans) +{ + struct i2c_control *control = i2c_bus->control; + u32 int_status; + u32 words; + u8 *dptr; + u32 local; + uchar last_bytes; + int error = 0; + int is_write = trans->flags & I2C_IS_WRITE; + + /* clear status from previous transaction, XFER_COMPLETE, NOACK, etc. */ + int_status = readl(&control->int_status); + writel(int_status, &control->int_status); + + send_packet_headers(i2c_bus, trans, 1); + + words = DIV_ROUND_UP(trans->num_bytes, 4); + last_bytes = trans->num_bytes & 3; + dptr = trans->buf; + + while (words) { + u32 *wptr = (u32 *)dptr; + + if (is_write) { + /* deal with word alignment */ + if ((unsigned)dptr & 3) { + memcpy(&local, dptr, sizeof(u32)); + writel(local, &control->tx_fifo); + debug("pkt data sent (0x%x)\n", local); + } else { + writel(*wptr, &control->tx_fifo); + debug("pkt data sent (0x%x)\n", *wptr); + } + if (!wait_for_tx_fifo_empty(control)) { + error = -1; + goto exit; + } + } else { + if (!wait_for_rx_fifo_notempty(control)) { + error = -1; + goto exit; + } + /* + * for the last word, we read into our local buffer, + * in case that caller did not provide enough buffer. + */ + local = readl(&control->rx_fifo); + if ((words == 1) && last_bytes) + memcpy(dptr, (char *)&local, last_bytes); + else if ((unsigned)dptr & 3) + memcpy(dptr, &local, sizeof(u32)); + else + *wptr = local; + debug("pkt data received (0x%x)\n", local); + } + words--; + dptr += sizeof(u32); + } + + if (wait_for_transfer_complete(control)) { + error = -1; + goto exit; + } + return 0; +exit: + /* error, reset the controller. */ + i2c_reset_controller(i2c_bus); + + return error; +} + +static int tegra2_i2c_write_data(u32 addr, u8 *data, u32 len) +{ + int error; + struct i2c_trans_info trans_info; + + trans_info.address = addr; + trans_info.buf = data; + trans_info.flags = I2C_IS_WRITE; + trans_info.num_bytes = len; + trans_info.is_10bit_address = 0; + + error = send_recv_packets(&i2c_controllers[i2c_bus_num], &trans_info); + if (error) + debug("tegra2_i2c_write_data: Error (%d) !!!\n", error); + + return error; +} + +static int tegra2_i2c_read_data(u32 addr, u8 *data, u32 len) +{ + int error; + struct i2c_trans_info trans_info; + + trans_info.address = addr | 1; + trans_info.buf = data; + trans_info.flags = 0; + trans_info.num_bytes = len; + trans_info.is_10bit_address = 0; + + error = send_recv_packets(&i2c_controllers[i2c_bus_num], &trans_info); + if (error) + debug("tegra2_i2c_read_data: Error (%d) !!!\n", error); + + return error; +} + +#ifndef CONFIG_OF_CONTROL +#error "Please enable device tree support to use this driver" +#endif + +unsigned int i2c_get_bus_speed(void) +{ + return i2c_controllers[i2c_bus_num].speed; +} + +int i2c_set_bus_speed(unsigned int speed) +{ + struct i2c_bus *i2c_bus; + + i2c_bus = &i2c_controllers[i2c_bus_num]; + i2c_bus->speed = speed; + i2c_init_controller(i2c_bus); + + return 0; +} + +static int i2c_get_config(const void *blob, int node, struct i2c_bus *i2c_bus) +{ + i2c_bus->regs = (struct i2c_ctlr *)fdtdec_get_addr(blob, node, "reg"); + + /* + * We don't have a binding for pinmux yet. Leave it out for now. So + * far no one needs anything other than the default. + */ + i2c_bus->pinmux_config = FUNCMUX_DEFAULT; + i2c_bus->speed = fdtdec_get_int(blob, node, "clock-frequency", 0); + i2c_bus->periph_id = clock_decode_periph_id(blob, node); + + /* + * We can't specify the pinmux config in the fdt, so I2C2 will not + * work on Seaboard. It normally has no devices on it anyway. + * You could add in this little hack if you need to use it. + * The correct solution is a pinmux binding in the fdt. + * + * if (i2c_bus->periph_id == PERIPH_ID_I2C2) + * i2c_bus->pinmux_config = FUNCMUX_I2C2_PTA; + */ + if (i2c_bus->periph_id == -1) + return -FDT_ERR_NOTFOUND; + + return 0; +} + +/* + * Process a list of nodes, adding them to our list of I2C ports. + * + * @param blob fdt blob + * @param node_list list of nodes to process (any <=0 are ignored) + * @param count number of nodes to process + * @param is_dvc 1 if these are DVC ports, 0 if standard I2C + * @return 0 if ok, -1 on error + */ +static int process_nodes(const void *blob, int node_list[], int count, + int is_dvc) +{ + struct i2c_bus *i2c_bus; + int i; + + /* build the i2c_controllers[] for each controller */ + for (i = 0; i < count; i++) { + int node = node_list[i]; + + if (node <= 0) + continue; + + i2c_bus = &i2c_controllers[i]; + i2c_bus->id = i; + + if (i2c_get_config(blob, node, i2c_bus)) { + printf("i2c_init_board: failed to decode bus %d\n", i); + return -1; + } + + i2c_bus->is_dvc = is_dvc; + if (is_dvc) { + i2c_bus->control = + &((struct dvc_ctlr *)i2c_bus->regs)->control; + } else { + i2c_bus->control = &i2c_bus->regs->control; + } + debug("%s: controller bus %d at %p, periph_id %d, speed %d: ", + is_dvc ? "dvc" : "i2c", i, i2c_bus->regs, + i2c_bus->periph_id, i2c_bus->speed); + i2c_init_controller(i2c_bus); + debug("ok\n"); + i2c_bus->inited = 1; + + /* Mark position as used */ + node_list[i] = -1; + } + + return 0; +} + +/* Sadly there is no error return from this function */ +void i2c_init_board(void) +{ + int node_list[TEGRA_I2C_NUM_CONTROLLERS]; + const void *blob = gd->fdt_blob; + int count; + + /* First get the normal i2c ports */ + count = fdtdec_find_aliases_for_id(blob, "i2c", + COMPAT_NVIDIA_TEGRA20_I2C, node_list, + TEGRA_I2C_NUM_CONTROLLERS); + if (process_nodes(blob, node_list, count, 0)) + return; + + /* Now look for dvc ports */ + count = fdtdec_add_aliases_for_id(blob, "i2c", + COMPAT_NVIDIA_TEGRA20_DVC, node_list, + TEGRA_I2C_NUM_CONTROLLERS); + if (process_nodes(blob, node_list, count, 1)) + return; +} + +void i2c_init(int speed, int slaveaddr) +{ + /* This will override the speed selected in the fdt for that port */ + debug("i2c_init(speed=%u, slaveaddr=0x%x)\n", speed, slaveaddr); + i2c_set_bus_speed(speed); +} + +/* i2c write version without the register address */ +int i2c_write_data(uchar chip, uchar *buffer, int len) +{ + int rc; + + debug("i2c_write_data: chip=0x%x, len=0x%x\n", chip, len); + debug("write_data: "); + /* use rc for counter */ + for (rc = 0; rc < len; ++rc) + debug(" 0x%02x", buffer[rc]); + debug("\n"); + + /* Shift 7-bit address over for lower-level i2c functions */ + rc = tegra2_i2c_write_data(chip << 1, buffer, len); + if (rc) + debug("i2c_write_data(): rc=%d\n", rc); + + return rc; +} + +/* i2c read version without the register address */ +int i2c_read_data(uchar chip, uchar *buffer, int len) +{ + int rc; + + debug("inside i2c_read_data():\n"); + /* Shift 7-bit address over for lower-level i2c functions */ + rc = tegra2_i2c_read_data(chip << 1, buffer, len); + if (rc) { + debug("i2c_read_data(): rc=%d\n", rc); + return rc; + } + + debug("i2c_read_data: "); + /* reuse rc for counter*/ + for (rc = 0; rc < len; ++rc) + debug(" 0x%02x", buffer[rc]); + debug("\n"); + + return 0; +} + +/* Probe to see if a chip is present. */ +int i2c_probe(uchar chip) +{ + int rc; + uchar reg; + + debug("i2c_probe: addr=0x%x\n", chip); + reg = 0; + rc = i2c_write_data(chip, ®, 1); + if (rc) { + debug("Error probing 0x%x.\n", chip); + return 1; + } + return 0; +} + +static int i2c_addr_ok(const uint addr, const int alen) +{ + /* We support 7 or 10 bit addresses, so one or two bytes each */ + return alen == 1 || alen == 2; +} + +/* Read bytes */ +int i2c_read(uchar chip, uint addr, int alen, uchar *buffer, int len) +{ + uint offset; + int i; + + debug("i2c_read: chip=0x%x, addr=0x%x, len=0x%x\n", + chip, addr, len); + if (!i2c_addr_ok(addr, alen)) { + debug("i2c_read: Bad address %x.%d.\n", addr, alen); + return 1; + } + for (offset = 0; offset < len; offset++) { + if (alen) { + uchar data[alen]; + for (i = 0; i < alen; i++) { + data[alen - i - 1] = + (addr + offset) >> (8 * i); + } + if (i2c_write_data(chip, data, alen)) { + debug("i2c_read: error sending (0x%x)\n", + addr); + return 1; + } + } + if (i2c_read_data(chip, buffer + offset, 1)) { + debug("i2c_read: error reading (0x%x)\n", addr); + return 1; + } + } + + return 0; +} + +/* Write bytes */ +int i2c_write(uchar chip, uint addr, int alen, uchar *buffer, int len) +{ + uint offset; + int i; + + debug("i2c_write: chip=0x%x, addr=0x%x, len=0x%x\n", + chip, addr, len); + if (!i2c_addr_ok(addr, alen)) { + debug("i2c_write: Bad address %x.%d.\n", addr, alen); + return 1; + } + for (offset = 0; offset < len; offset++) { + uchar data[alen + 1]; + for (i = 0; i < alen; i++) + data[alen - i - 1] = (addr + offset) >> (8 * i); + data[alen] = buffer[offset]; + if (i2c_write_data(chip, data, alen + 1)) { + debug("i2c_write: error sending (0x%x)\n", addr); + return 1; + } + } + + return 0; +} + +#if defined(CONFIG_I2C_MULTI_BUS) +/* + * Functions for multiple I2C bus handling + */ +unsigned int i2c_get_bus_num(void) +{ + return i2c_bus_num; +} + +int i2c_set_bus_num(unsigned int bus) +{ + if (bus >= TEGRA_I2C_NUM_CONTROLLERS || !i2c_controllers[bus].inited) + return -1; + i2c_bus_num = bus; + + return 0; +} +#endif |