/*- * Copyright (c) 2011 Ben Gray . * Copyright (c) 2014 Luiz Otavio O Souza . * All rights reserved. * * Redistribution and use in source and binary forms, with or without * modification, are permitted provided that the following conditions * are met: * 1. Redistributions of source code must retain the above copyright * notice, this list of conditions and the following disclaimer. * 2. Redistributions in binary form must reproduce the above copyright * notice, this list of conditions and the following disclaimer in the * documentation and/or other materials provided with the distribution. * * THIS SOFTWARE IS PROVIDED BY AUTHOR AND CONTRIBUTORS ``AS IS'' AND * ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE * IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE * ARE DISCLAIMED. IN NO EVENT SHALL AUTHOR OR CONTRIBUTORS BE LIABLE * FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL * DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS * OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION) * HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT * LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY * OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF * SUCH DAMAGE. */ /** * Driver for the I2C module on the TI SoC. * * This driver is heavily based on the TWI driver for the AT91 (at91_twi.c). * * CAUTION: The I2Ci registers are limited to 16 bit and 8 bit data accesses, * 32 bit data access is not allowed and can corrupt register content. * * This driver currently doesn't use DMA for the transfer, although I hope to * incorporate that sometime in the future. The idea being that for transaction * larger than a certain size the DMA engine is used, for anything less the * normal interrupt/fifo driven option is used. * * * WARNING: This driver uses mtx_sleep and interrupts to perform transactions, * which means you can't do a transaction during startup before the interrupts * have been enabled. Hint - the freebsd function config_intrhook_establish(). */ #include __FBSDID("$FreeBSD$"); #include #include #include #include #include #include #include #include #include #include #include #include #include #include #include #include #include #include #include #include #include #include "iicbus_if.h" /** * I2C device driver context, a pointer to this is stored in the device * driver structure. */ struct ti_i2c_softc { device_t sc_dev; uint32_t device_id; struct resource* sc_irq_res; struct resource* sc_mem_res; device_t sc_iicbus; void* sc_irq_h; struct mtx sc_mtx; struct iic_msg* sc_buffer; int sc_bus_inuse; int sc_buffer_pos; int sc_error; int sc_fifo_trsh; uint16_t sc_con_reg; uint16_t sc_rev; }; struct ti_i2c_clock_config { int speed; int bitrate; uint8_t psc; /* Fast/Standard mode prescale divider */ uint8_t scll; /* Fast/Standard mode SCL low time */ uint8_t sclh; /* Fast/Standard mode SCL high time */ uint8_t hsscll; /* High Speed mode SCL low time */ uint8_t hssclh; /* High Speed mode SCL high time */ }; #if defined(SOC_OMAP4) static struct ti_i2c_clock_config ti_omap4_i2c_clock_configs[] = { { IIC_UNKNOWN, 100000, 23, 13, 15, 0, 0}, { IIC_SLOW, 100000, 23, 13, 15, 0, 0}, { IIC_FAST, 400000, 9, 5, 7, 0, 0}, { IIC_FASTEST, 1000000, 5, 3, 4, 0, 0}, /* { IIC_FASTEST, 3200000, 1, 113, 115, 7, 10}, - HS mode */ { -1, 0 } }; #endif #if defined(SOC_TI_AM335X) /* * AM335X doesn't support HS mode. For 100kHz I2C clock set the internal * clock to 12Mhz, for 400kHz I2C clock set the internal clock to 24Mhz. */ static struct ti_i2c_clock_config ti_am335x_i2c_clock_configs[] = { { IIC_UNKNOWN, 100000, 7, 59, 61, 0, 0}, { IIC_SLOW, 100000, 7, 59, 61, 0, 0}, { IIC_FAST, 400000, 3, 23, 25, 0, 0}, { IIC_FASTEST, 400000, 3, 23, 25, 0, 0}, { -1, 0 } }; #endif /** * Locking macros used throughout the driver */ #define TI_I2C_LOCK(_sc) mtx_lock(&(_sc)->sc_mtx) #define TI_I2C_UNLOCK(_sc) mtx_unlock(&(_sc)->sc_mtx) #define TI_I2C_LOCK_INIT(_sc) \ mtx_init(&_sc->sc_mtx, device_get_nameunit(_sc->sc_dev), \ "ti_i2c", MTX_DEF) #define TI_I2C_LOCK_DESTROY(_sc) mtx_destroy(&_sc->sc_mtx) #define TI_I2C_ASSERT_LOCKED(_sc) mtx_assert(&_sc->sc_mtx, MA_OWNED) #define TI_I2C_ASSERT_UNLOCKED(_sc) mtx_assert(&_sc->sc_mtx, MA_NOTOWNED) #ifdef DEBUG #define ti_i2c_dbg(_sc, fmt, args...) \ device_printf((_sc)->sc_dev, fmt, ##args) #else #define ti_i2c_dbg(_sc, fmt, args...) #endif /** * ti_i2c_read_2 - reads a 16-bit value from one of the I2C registers * @sc: I2C device context * @off: the byte offset within the register bank to read from. * * * LOCKING: * No locking required * * RETURNS: * 16-bit value read from the register. */ static inline uint16_t ti_i2c_read_2(struct ti_i2c_softc *sc, bus_size_t off) { return (bus_read_2(sc->sc_mem_res, off)); } /** * ti_i2c_write_2 - writes a 16-bit value to one of the I2C registers * @sc: I2C device context * @off: the byte offset within the register bank to read from. * @val: the value to write into the register * * LOCKING: * No locking required * * RETURNS: * 16-bit value read from the register. */ static inline void ti_i2c_write_2(struct ti_i2c_softc *sc, bus_size_t off, uint16_t val) { bus_write_2(sc->sc_mem_res, off, val); } static int ti_i2c_transfer_intr(struct ti_i2c_softc* sc, uint16_t status) { int amount, done, i; done = 0; amount = 0; /* Check for the error conditions. */ if (status & I2C_STAT_NACK) { /* No ACK from slave. */ ti_i2c_dbg(sc, "NACK\n"); ti_i2c_write_2(sc, I2C_REG_STATUS, I2C_STAT_NACK); sc->sc_error = ENXIO; } else if (status & I2C_STAT_AL) { /* Arbitration lost. */ ti_i2c_dbg(sc, "Arbitration lost\n"); ti_i2c_write_2(sc, I2C_REG_STATUS, I2C_STAT_AL); sc->sc_error = ENXIO; } /* Check if we have finished. */ if (status & I2C_STAT_ARDY) { /* Register access ready - transaction complete basically. */ ti_i2c_dbg(sc, "ARDY transaction complete\n"); if (sc->sc_error != 0 && sc->sc_buffer->flags & IIC_M_NOSTOP) { ti_i2c_write_2(sc, I2C_REG_CON, sc->sc_con_reg | I2C_CON_STP); } ti_i2c_write_2(sc, I2C_REG_STATUS, I2C_STAT_ARDY | I2C_STAT_RDR | I2C_STAT_RRDY | I2C_STAT_XDR | I2C_STAT_XRDY); return (1); } if (sc->sc_buffer->flags & IIC_M_RD) { /* Read some data. */ if (status & I2C_STAT_RDR) { /* * Receive draining interrupt - last data received. * The set FIFO threshold wont be reached to trigger * RRDY. */ ti_i2c_dbg(sc, "Receive draining interrupt\n"); /* * Drain the FIFO. Read the pending data in the FIFO. */ amount = sc->sc_buffer->len - sc->sc_buffer_pos; } else if (status & I2C_STAT_RRDY) { /* * Receive data ready interrupt - FIFO has reached the * set threshold. */ ti_i2c_dbg(sc, "Receive data ready interrupt\n"); amount = min(sc->sc_fifo_trsh, sc->sc_buffer->len - sc->sc_buffer_pos); } /* Read the bytes from the fifo. */ for (i = 0; i < amount; i++) sc->sc_buffer->buf[sc->sc_buffer_pos++] = (uint8_t)(ti_i2c_read_2(sc, I2C_REG_DATA) & 0xff); if (status & I2C_STAT_RDR) ti_i2c_write_2(sc, I2C_REG_STATUS, I2C_STAT_RDR); if (status & I2C_STAT_RRDY) ti_i2c_write_2(sc, I2C_REG_STATUS, I2C_STAT_RRDY); } else { /* Write some data. */ if (status & I2C_STAT_XDR) { /* * Transmit draining interrupt - FIFO level is below * the set threshold and the amount of data still to * be transferred wont reach the set FIFO threshold. */ ti_i2c_dbg(sc, "Transmit draining interrupt\n"); /* * Drain the TX data. Write the pending data in the * FIFO. */ amount = sc->sc_buffer->len - sc->sc_buffer_pos; } else if (status & I2C_STAT_XRDY) { /* * Transmit data ready interrupt - the FIFO level * is below the set threshold. */ ti_i2c_dbg(sc, "Transmit data ready interrupt\n"); amount = min(sc->sc_fifo_trsh, sc->sc_buffer->len - sc->sc_buffer_pos); } /* Write the bytes from the fifo. */ for (i = 0; i < amount; i++) ti_i2c_write_2(sc, I2C_REG_DATA, sc->sc_buffer->buf[sc->sc_buffer_pos++]); if (status & I2C_STAT_XDR) ti_i2c_write_2(sc, I2C_REG_STATUS, I2C_STAT_XDR); if (status & I2C_STAT_XRDY) ti_i2c_write_2(sc, I2C_REG_STATUS, I2C_STAT_XRDY); } return (done); } /** * ti_i2c_intr - interrupt handler for the I2C module * @dev: i2c device handle * * * * LOCKING: * Called from timer context * * RETURNS: * EH_HANDLED or EH_NOT_HANDLED */ static void ti_i2c_intr(void *arg) { int done; struct ti_i2c_softc *sc; uint16_t events, status; sc = (struct ti_i2c_softc *)arg; TI_I2C_LOCK(sc); status = ti_i2c_read_2(sc, I2C_REG_STATUS); if (status == 0) { TI_I2C_UNLOCK(sc); return; } /* Save enabled interrupts. */ events = ti_i2c_read_2(sc, I2C_REG_IRQENABLE_SET); /* We only care about enabled interrupts. */ status &= events; done = 0; if (sc->sc_buffer != NULL) done = ti_i2c_transfer_intr(sc, status); else { ti_i2c_dbg(sc, "Transfer interrupt without buffer\n"); sc->sc_error = EINVAL; done = 1; } if (done) /* Wakeup the process that started the transaction. */ wakeup(sc); TI_I2C_UNLOCK(sc); } /** * ti_i2c_transfer - called to perform the transfer * @dev: i2c device handle * @msgs: the messages to send/receive * @nmsgs: the number of messages in the msgs array * * * LOCKING: * Internally locked * * RETURNS: * 0 on function succeeded * EINVAL if invalid message is passed as an arg */ static int ti_i2c_transfer(device_t dev, struct iic_msg *msgs, uint32_t nmsgs) { int err, i, repstart, timeout; struct ti_i2c_softc *sc; uint16_t reg; sc = device_get_softc(dev); TI_I2C_LOCK(sc); /* If the controller is busy wait until it is available. */ while (sc->sc_bus_inuse == 1) mtx_sleep(sc, &sc->sc_mtx, 0, "i2cbuswait", 0); /* Now we have control over the I2C controller. */ sc->sc_bus_inuse = 1; err = 0; repstart = 0; for (i = 0; i < nmsgs; i++) { sc->sc_buffer = &msgs[i]; sc->sc_buffer_pos = 0; sc->sc_error = 0; /* Zero byte transfers aren't allowed. */ if (sc->sc_buffer == NULL || sc->sc_buffer->buf == NULL || sc->sc_buffer->len == 0) { err = EINVAL; break; } /* Check if the i2c bus is free. */ if (repstart == 0) { /* * On repeated start we send the START condition while * the bus _is_ busy. */ timeout = 0; while (ti_i2c_read_2(sc, I2C_REG_STATUS_RAW) & I2C_STAT_BB) { if (timeout++ > 100) { err = EBUSY; goto out; } DELAY(1000); } timeout = 0; } else repstart = 0; if (sc->sc_buffer->flags & IIC_M_NOSTOP) repstart = 1; /* Set the slave address. */ ti_i2c_write_2(sc, I2C_REG_SA, msgs[i].slave >> 1); /* Write the data length. */ ti_i2c_write_2(sc, I2C_REG_CNT, sc->sc_buffer->len); /* Clear the RX and the TX FIFO. */ reg = ti_i2c_read_2(sc, I2C_REG_BUF); reg |= I2C_BUF_RXFIFO_CLR | I2C_BUF_TXFIFO_CLR; ti_i2c_write_2(sc, I2C_REG_BUF, reg); reg = sc->sc_con_reg | I2C_CON_STT; if (repstart == 0) reg |= I2C_CON_STP; if ((sc->sc_buffer->flags & IIC_M_RD) == 0) reg |= I2C_CON_TRX; ti_i2c_write_2(sc, I2C_REG_CON, reg); /* Wait for an event. */ err = mtx_sleep(sc, &sc->sc_mtx, 0, "i2ciowait", hz); if (err == 0) err = sc->sc_error; if (err) break; } out: if (timeout == 0) { while (ti_i2c_read_2(sc, I2C_REG_STATUS_RAW) & I2C_STAT_BB) { if (timeout++ > 100) break; DELAY(1000); } } /* Put the controller in master mode again. */ if ((ti_i2c_read_2(sc, I2C_REG_CON) & I2C_CON_MST) == 0) ti_i2c_write_2(sc, I2C_REG_CON, sc->sc_con_reg); sc->sc_buffer = NULL; sc->sc_bus_inuse = 0; /* Wake up the processes that are waiting for the bus. */ wakeup(sc); TI_I2C_UNLOCK(sc); return (err); } /** * ti_i2c_callback - as we only provide iicbus_transfer() interface * we don't need to implement the serialization here. * @dev: i2c device handle * * * * LOCKING: * Called from timer context * * RETURNS: * EH_HANDLED or EH_NOT_HANDLED */ static int ti_i2c_callback(device_t dev, int index, caddr_t data) { int error = 0; switch (index) { case IIC_REQUEST_BUS: break; case IIC_RELEASE_BUS: break; default: error = EINVAL; } return (error); } static int ti_i2c_reset(struct ti_i2c_softc *sc, u_char speed) { int timeout; struct ti_i2c_clock_config *clkcfg; uint16_t fifo_trsh, reg, scll, sclh; switch (ti_chip()) { #ifdef SOC_OMAP4 case CHIP_OMAP_4: clkcfg = ti_omap4_i2c_clock_configs; break; #endif #ifdef SOC_TI_AM335X case CHIP_AM335X: clkcfg = ti_am335x_i2c_clock_configs; break; #endif default: panic("Unknown Ti SoC, unable to reset the i2c"); } while (clkcfg->speed != -1) { if (clkcfg->speed == speed) break; clkcfg++; } if (clkcfg->speed == -1) return (EINVAL); /* * 23.1.4.3 - HS I2C Software Reset * From OMAP4 TRM at page 4068. * * 1. Ensure that the module is disabled. */ sc->sc_con_reg = 0; ti_i2c_write_2(sc, I2C_REG_CON, sc->sc_con_reg); /* 2. Issue a softreset to the controller. */ bus_write_2(sc->sc_mem_res, I2C_REG_SYSC, I2C_REG_SYSC_SRST); /* * 3. Enable the module. * The I2Ci.I2C_SYSS[0] RDONE bit is asserted only after the module * is enabled by setting the I2Ci.I2C_CON[15] I2C_EN bit to 1. */ ti_i2c_write_2(sc, I2C_REG_CON, I2C_CON_I2C_EN); /* 4. Wait for the software reset to complete. */ timeout = 0; while ((ti_i2c_read_2(sc, I2C_REG_SYSS) & I2C_SYSS_RDONE) == 0) { if (timeout++ > 100) return (EBUSY); DELAY(100); } /* * Disable the I2C controller once again, now that the reset has * finished. */ ti_i2c_write_2(sc, I2C_REG_CON, sc->sc_con_reg); /* * The following sequence is taken from the OMAP4 TRM at page 4077. * * 1. Enable the functional and interface clocks (see Section * 23.1.5.1.1.1.1). Done at ti_i2c_activate(). * * 2. Program the prescaler to obtain an approximately 12MHz internal * sampling clock (I2Ci_INTERNAL_CLK) by programming the * corresponding value in the I2Ci.I2C_PSC[3:0] PSC field. * This value depends on the frequency of the functional clock * (I2Ci_FCLK). Because this frequency is 96MHz, the * I2Ci.I2C_PSC[7:0] PSC field value is 0x7. */ ti_i2c_write_2(sc, I2C_REG_PSC, clkcfg->psc); /* * 3. Program the I2Ci.I2C_SCLL[7:0] SCLL and I2Ci.I2C_SCLH[7:0] SCLH * bit fields to obtain a bit rate of 100 Kbps, 400 Kbps or 1Mbps. * These values depend on the internal sampling clock frequency * (see Table 23-8). */ scll = clkcfg->scll & I2C_SCLL_MASK; sclh = clkcfg->sclh & I2C_SCLH_MASK; /* * 4. (Optional) Program the I2Ci.I2C_SCLL[15:8] HSSCLL and * I2Ci.I2C_SCLH[15:8] HSSCLH fields to obtain a bit rate of * 400K bps or 3.4M bps (for the second phase of HS mode). These * values depend on the internal sampling clock frequency (see * Table 23-8). * * 5. (Optional) If a bit rate of 3.4M bps is used and the bus line * capacitance exceeds 45 pF, (see Section 18.4.8, PAD Functional * Multiplexing and Configuration). */ switch (ti_chip()) { #ifdef SOC_OMAP4 case CHIP_OMAP_4: if ((clkcfg->hsscll + clkcfg->hssclh) > 0) { scll |= clkcfg->hsscll << I2C_HSSCLL_SHIFT; sclh |= clkcfg->hssclh << I2C_HSSCLH_SHIFT; sc->sc_con_reg |= I2C_CON_OPMODE_HS; } break; #endif } /* Write the selected bit rate. */ ti_i2c_write_2(sc, I2C_REG_SCLL, scll); ti_i2c_write_2(sc, I2C_REG_SCLH, sclh); /* * 6. Configure the Own Address of the I2C controller by storing it in * the I2Ci.I2C_OA0 register. Up to four Own Addresses can be * programmed in the I2Ci.I2C_OAi registers (where i = 0, 1, 2, 3) * for each I2C controller. * * Note: For a 10-bit address, set the corresponding expand Own Address * bit in the I2Ci.I2C_CON register. * * Driver currently always in single master mode so ignore this step. */ /* * 7. Set the TX threshold (in transmitter mode) and the RX threshold * (in receiver mode) by setting the I2Ci.I2C_BUF[5:0]XTRSH field to * (TX threshold - 1) and the I2Ci.I2C_BUF[13:8]RTRSH field to (RX * threshold - 1), where the TX and RX thresholds are greater than * or equal to 1. * * The threshold is set to 5 for now. */ fifo_trsh = (sc->sc_fifo_trsh - 1) & I2C_BUF_TRSH_MASK; reg = fifo_trsh | (fifo_trsh << I2C_BUF_RXTRSH_SHIFT); ti_i2c_write_2(sc, I2C_REG_BUF, reg); /* * 8. Take the I2C controller out of reset by setting the * I2Ci.I2C_CON[15] I2C_EN bit to 1. * * 23.1.5.1.1.1.2 - Initialize the I2C Controller * * To initialize the I2C controller, perform the following steps: * * 1. Configure the I2Ci.I2C_CON register: * . For master or slave mode, set the I2Ci.I2C_CON[10] MST bit * (0: slave, 1: master). * . For transmitter or receiver mode, set the I2Ci.I2C_CON[9] TRX * bit (0: receiver, 1: transmitter). */ /* Enable the I2C controller in master mode. */ sc->sc_con_reg |= I2C_CON_I2C_EN | I2C_CON_MST; ti_i2c_write_2(sc, I2C_REG_CON, sc->sc_con_reg); /* * 2. If using an interrupt to transmit/receive data, set the * corresponding bit in the I2Ci.I2C_IE register (the I2Ci.I2C_IE[4] * XRDY_IE bit for the transmit interrupt, the I2Ci.I2C_IE[3] RRDY * bit for the receive interrupt). */ /* Set the interrupts we want to be notified. */ reg = I2C_IE_XDR | /* Transmit draining interrupt. */ I2C_IE_XRDY | /* Transmit Data Ready interrupt. */ I2C_IE_RDR | /* Receive draining interrupt. */ I2C_IE_RRDY | /* Receive Data Ready interrupt. */ I2C_IE_ARDY | /* Register Access Ready interrupt. */ I2C_IE_NACK | /* No Acknowledgment interrupt. */ I2C_IE_AL; /* Arbitration lost interrupt. */ /* Enable the interrupts. */ ti_i2c_write_2(sc, I2C_REG_IRQENABLE_SET, reg); /* * 3. If using DMA to receive/transmit data, set to 1 the corresponding * bit in the I2Ci.I2C_BUF register (the I2Ci.I2C_BUF[15] RDMA_EN * bit for the receive DMA channel, the I2Ci.I2C_BUF[7] XDMA_EN bit * for the transmit DMA channel). * * Not using DMA for now, so ignore this. */ return (0); } static int ti_i2c_iicbus_reset(device_t dev, u_char speed, u_char addr, u_char *oldaddr) { struct ti_i2c_softc *sc; int err; sc = device_get_softc(dev); TI_I2C_LOCK(sc); err = ti_i2c_reset(sc, speed); TI_I2C_UNLOCK(sc); if (err) return (err); return (IIC_ENOADDR); } static int ti_i2c_activate(device_t dev) { clk_ident_t clk; int err; struct ti_i2c_softc *sc; sc = (struct ti_i2c_softc*)device_get_softc(dev); /* * 1. Enable the functional and interface clocks (see Section * 23.1.5.1.1.1.1). */ clk = I2C0_CLK + sc->device_id; err = ti_prcm_clk_enable(clk); if (err) return (err); return (ti_i2c_reset(sc, IIC_UNKNOWN)); } /** * ti_i2c_deactivate - deactivates the controller and releases resources * @dev: i2c device handle * * * * LOCKING: * Assumed called in an atomic context. * * RETURNS: * nothing */ static void ti_i2c_deactivate(device_t dev) { struct ti_i2c_softc *sc = device_get_softc(dev); clk_ident_t clk; /* Disable the controller - cancel all transactions. */ ti_i2c_write_2(sc, I2C_REG_IRQENABLE_CLR, 0xffff); ti_i2c_write_2(sc, I2C_REG_STATUS, 0xffff); ti_i2c_write_2(sc, I2C_REG_CON, 0); /* Release the interrupt handler. */ if (sc->sc_irq_h != NULL) { bus_teardown_intr(dev, sc->sc_irq_res, sc->sc_irq_h); sc->sc_irq_h = NULL; } bus_generic_detach(sc->sc_dev); /* Unmap the I2C controller registers. */ if (sc->sc_mem_res != NULL) { bus_release_resource(dev, SYS_RES_MEMORY, 0, sc->sc_mem_res); sc->sc_mem_res = NULL; } /* Release the IRQ resource. */ if (sc->sc_irq_res != NULL) { bus_release_resource(dev, SYS_RES_IRQ, 0, sc->sc_irq_res); sc->sc_irq_res = NULL; } /* Finally disable the functional and interface clocks. */ clk = I2C0_CLK + sc->device_id; ti_prcm_clk_disable(clk); } static int ti_i2c_sysctl_clk(SYSCTL_HANDLER_ARGS) { device_t dev; int clk, psc, sclh, scll; struct ti_i2c_softc *sc; dev = (device_t)arg1; sc = device_get_softc(dev); TI_I2C_LOCK(sc); /* Get the system prescaler value. */ psc = (int)ti_i2c_read_2(sc, I2C_REG_PSC) + 1; /* Get the bitrate. */ scll = (int)ti_i2c_read_2(sc, I2C_REG_SCLL) & I2C_SCLL_MASK; sclh = (int)ti_i2c_read_2(sc, I2C_REG_SCLH) & I2C_SCLH_MASK; clk = I2C_CLK / psc / (scll + 7 + sclh + 5); TI_I2C_UNLOCK(sc); return (sysctl_handle_int(oidp, &clk, 0, req)); } static int ti_i2c_probe(device_t dev) { if (!ofw_bus_status_okay(dev)) return (ENXIO); if (!ofw_bus_is_compatible(dev, "ti,i2c")) return (ENXIO); device_set_desc(dev, "TI I2C Controller"); return (0); } static int ti_i2c_attach(device_t dev) { int err, rid; phandle_t node; struct ti_i2c_softc *sc; struct sysctl_ctx_list *ctx; struct sysctl_oid_list *tree; uint16_t fifosz; sc = device_get_softc(dev); sc->sc_dev = dev; /* Get the i2c device id from FDT. */ node = ofw_bus_get_node(dev); if ((OF_getencprop(node, "i2c-device-id", &sc->device_id, sizeof(sc->device_id))) <= 0) { device_printf(dev, "missing i2c-device-id attribute in FDT\n"); return (ENXIO); } /* Get the memory resource for the register mapping. */ rid = 0; sc->sc_mem_res = bus_alloc_resource_any(dev, SYS_RES_MEMORY, &rid, RF_ACTIVE); if (sc->sc_mem_res == NULL) { device_printf(dev, "Cannot map registers.\n"); return (ENXIO); } /* Allocate our IRQ resource. */ rid = 0; sc->sc_irq_res = bus_alloc_resource_any(dev, SYS_RES_IRQ, &rid, RF_ACTIVE | RF_SHAREABLE); if (sc->sc_irq_res == NULL) { bus_release_resource(dev, SYS_RES_MEMORY, 0, sc->sc_mem_res); device_printf(dev, "Cannot allocate interrupt.\n"); return (ENXIO); } TI_I2C_LOCK_INIT(sc); /* First of all, we _must_ activate the H/W. */ err = ti_i2c_activate(dev); if (err) { device_printf(dev, "ti_i2c_activate failed\n"); goto out; } /* Read the version number of the I2C module */ sc->sc_rev = ti_i2c_read_2(sc, I2C_REG_REVNB_HI) & 0xff; /* Get the fifo size. */ fifosz = ti_i2c_read_2(sc, I2C_REG_BUFSTAT); fifosz >>= I2C_BUFSTAT_FIFODEPTH_SHIFT; fifosz &= I2C_BUFSTAT_FIFODEPTH_MASK; device_printf(dev, "I2C revision %d.%d FIFO size: %d bytes\n", sc->sc_rev >> 4, sc->sc_rev & 0xf, 8 << fifosz); /* Set the FIFO threshold to 5 for now. */ sc->sc_fifo_trsh = 5; ctx = device_get_sysctl_ctx(dev); tree = SYSCTL_CHILDREN(device_get_sysctl_tree(dev)); SYSCTL_ADD_PROC(ctx, tree, OID_AUTO, "i2c_clock", CTLFLAG_RD | CTLTYPE_UINT | CTLFLAG_MPSAFE, dev, 0, ti_i2c_sysctl_clk, "IU", "I2C bus clock"); /* Activate the interrupt. */ err = bus_setup_intr(dev, sc->sc_irq_res, INTR_TYPE_MISC | INTR_MPSAFE, NULL, ti_i2c_intr, sc, &sc->sc_irq_h); if (err) goto out; /* Attach the iicbus. */ if ((sc->sc_iicbus = device_add_child(dev, "iicbus", -1)) == NULL) { device_printf(dev, "could not allocate iicbus instance\n"); err = ENXIO; goto out; } /* Probe and attach the iicbus */ bus_generic_attach(dev); out: if (err) { ti_i2c_deactivate(dev); TI_I2C_LOCK_DESTROY(sc); } return (err); } static int ti_i2c_detach(device_t dev) { struct ti_i2c_softc *sc; int rv; sc = device_get_softc(dev); ti_i2c_deactivate(dev); TI_I2C_LOCK_DESTROY(sc); if (sc->sc_iicbus && (rv = device_delete_child(dev, sc->sc_iicbus)) != 0) return (rv); return (0); } static phandle_t ti_i2c_get_node(device_t bus, device_t dev) { /* Share controller node with iibus device. */ return (ofw_bus_get_node(bus)); } static device_method_t ti_i2c_methods[] = { /* Device interface */ DEVMETHOD(device_probe, ti_i2c_probe), DEVMETHOD(device_attach, ti_i2c_attach), DEVMETHOD(device_detach, ti_i2c_detach), /* OFW methods */ DEVMETHOD(ofw_bus_get_node, ti_i2c_get_node), /* iicbus interface */ DEVMETHOD(iicbus_callback, ti_i2c_callback), DEVMETHOD(iicbus_reset, ti_i2c_iicbus_reset), DEVMETHOD(iicbus_transfer, ti_i2c_transfer), DEVMETHOD_END }; static driver_t ti_i2c_driver = { "iichb", ti_i2c_methods, sizeof(struct ti_i2c_softc), }; static devclass_t ti_i2c_devclass; DRIVER_MODULE(ti_iic, simplebus, ti_i2c_driver, ti_i2c_devclass, 0, 0); DRIVER_MODULE(iicbus, ti_iic, iicbus_driver, iicbus_devclass, 0, 0); MODULE_DEPEND(ti_iic, ti_prcm, 1, 1, 1); MODULE_DEPEND(ti_iic, iicbus, 1, 1, 1);