/* * 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/clock.h> #include <asm/arch/funcmux.h> #include <asm/arch/gpio.h> #include <asm/arch/pinmux.h> #include <asm/arch-tegra/clk_rst.h> #include <asm/arch-tegra/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 tegra_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("tegra_i2c_write_data: Error (%d) !!!\n", error); return error; } static int tegra_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("tegra_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 = tegra_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 = tegra_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 int tegra_i2c_get_dvc_bus_num(void) { int i; for (i = 0; i < CONFIG_SYS_MAX_I2C_BUS; i++) { struct i2c_bus *bus = &i2c_controllers[i]; if (bus->inited && bus->is_dvc) return i; } return -1; }