From 59e21a2ab9b7554acf2c15dc9ee191e76bebade7 Mon Sep 17 00:00:00 2001 From: John Crispin Date: Fri, 4 Nov 2011 16:00:34 +0100 Subject: [PATCH 36/70] I2C: MIPS: lantiq: add FALC-ON i2c bus master This patch adds the driver needed to make the I2C bus work on FALC-ON SoCs. Signed-off-by: Thomas Langer Signed-off-by: John Crispin Cc: linux-i2c@vger.kernel.org --- .../include/asm/mach-lantiq/falcon/lantiq_soc.h | 5 + arch/mips/lantiq/falcon/clk.c | 44 - arch/mips/lantiq/falcon/devices.c | 16 + arch/mips/lantiq/falcon/devices.h | 1 + arch/mips/lantiq/falcon/mach-easy98000.c | 1 + drivers/i2c/busses/Kconfig | 10 + drivers/i2c/busses/Makefile | 1 + drivers/i2c/busses/i2c-falcon.c | 1040 ++++++++++++++++++++ 8 files changed, 1074 insertions(+), 44 deletions(-) delete mode 100644 arch/mips/lantiq/falcon/clk.c create mode 100644 drivers/i2c/busses/i2c-falcon.c --- a/arch/mips/include/asm/mach-lantiq/falcon/lantiq_soc.h +++ b/arch/mips/include/asm/mach-lantiq/falcon/lantiq_soc.h @@ -72,6 +72,10 @@ #define LTQ_PADCTRL4_BASE_ADDR 0x1E800600 #define LTQ_PADCTRL4_SIZE 0x0100 +/* I2C */ +#define GPON_I2C_BASE 0x1E200000 +#define GPON_I2C_SIZE 0x00010000 + /* CHIP ID */ #define LTQ_STATUS_BASE_ADDR 0x1E802000 @@ -106,6 +110,7 @@ #define ACTS_PADCTRL2 0x00200000 #define ACTS_PADCTRL3 0x00200000 #define ACTS_PADCTRL4 0x00400000 +#define ACTS_I2C_ACT 0x00004000 /* global register ranges */ extern __iomem void *ltq_ebu_membase; --- a/arch/mips/lantiq/falcon/clk.c +++ /dev/null @@ -1,44 +0,0 @@ -/* - * This program is free software; you can redistribute it and/or modify it - * under the terms of the GNU General Public License version 2 as published - * by the Free Software Foundation. - * - * Copyright (C) 2011 Thomas Langer - * Copyright (C) 2011 John Crispin - */ - -#include -#include - -#include - -#include "devices.h" - -/* CPU0 Clock Control Register */ -#define LTQ_SYS1_CPU0CC 0x0040 -/* clock divider bit */ -#define LTQ_CPU0CC_CPUDIV 0x0001 - -unsigned int -ltq_get_io_region_clock(void) -{ - return CLOCK_200M; -} -EXPORT_SYMBOL(ltq_get_io_region_clock); - -unsigned int -ltq_get_cpu_hz(void) -{ - if (ltq_sys1_r32(LTQ_SYS1_CPU0CC) & LTQ_CPU0CC_CPUDIV) - return CLOCK_200M; - else - return CLOCK_400M; -} -EXPORT_SYMBOL(ltq_get_cpu_hz); - -unsigned int -ltq_get_fpi_hz(void) -{ - return CLOCK_100M; -} -EXPORT_SYMBOL(ltq_get_fpi_hz); --- a/arch/mips/lantiq/falcon/devices.c +++ b/arch/mips/lantiq/falcon/devices.c @@ -134,3 +134,19 @@ falcon_register_spi_flash(struct spi_boa spi_register_board_info(data, 1); platform_device_register(<q_spi); } + +/* i2c */ +static struct resource falcon_i2c_resources[] = { + MEM_RES("i2c", GPON_I2C_BASE, GPON_I2C_SIZE), + IRQ_RES(i2c_lb, FALCON_IRQ_I2C_LBREQ), + IRQ_RES(i2c_b, FALCON_IRQ_I2C_BREQ), + IRQ_RES(i2c_err, FALCON_IRQ_I2C_I2C_ERR), + IRQ_RES(i2c_p, FALCON_IRQ_I2C_I2C_P), +}; + +void __init +falcon_register_i2c(void) +{ + platform_device_register_simple("i2c-falcon", 0, + falcon_i2c_resources, ARRAY_SIZE(falcon_i2c_resources)); +} --- a/arch/mips/lantiq/falcon/devices.h +++ b/arch/mips/lantiq/falcon/devices.h @@ -20,5 +20,6 @@ extern void falcon_register_nand(void); extern void falcon_register_gpio(void); extern void falcon_register_gpio_extra(void); extern void falcon_register_spi_flash(struct spi_board_info *data); +extern void falcon_register_i2c(void); #endif --- a/arch/mips/lantiq/falcon/mach-easy98000.c +++ b/arch/mips/lantiq/falcon/mach-easy98000.c @@ -98,6 +98,7 @@ easy98000_init_common(void) { spi_register_board_info(&easy98000_spi_gpio_devices, 1); platform_device_register(&easy98000_spi_gpio_device); + falcon_register_i2c(); } static void __init --- a/drivers/i2c/busses/Kconfig +++ b/drivers/i2c/busses/Kconfig @@ -369,6 +369,16 @@ config I2C_DESIGNWARE_PCI This driver can also be built as a module. If so, the module will be called i2c-designware-pci. +config I2C_FALCON + tristate "Falcon I2C interface" + depends on SOC_FALCON + help + If you say yes to this option, support will be included for the + Lantiq FALC-ON I2C core. + + This driver can also be built as a module. If so, the module + will be called i2c-falcon. + config I2C_GPIO tristate "GPIO-based bitbanging I2C" depends on GENERIC_GPIO --- a/drivers/i2c/busses/Makefile +++ b/drivers/i2c/busses/Makefile @@ -37,6 +37,7 @@ obj-$(CONFIG_I2C_DESIGNWARE_PLATFORM) += i2c-designware-platform-objs := i2c-designware-platdrv.o i2c-designware-core.o obj-$(CONFIG_I2C_DESIGNWARE_PCI) += i2c-designware-pci.o i2c-designware-pci-objs := i2c-designware-pcidrv.o i2c-designware-core.o +obj-$(CONFIG_I2C_FALCON) += i2c-falcon.o obj-$(CONFIG_I2C_GPIO) += i2c-gpio.o obj-$(CONFIG_I2C_HIGHLANDER) += i2c-highlander.o obj-$(CONFIG_I2C_IBM_IIC) += i2c-ibm_iic.o --- /dev/null +++ b/drivers/i2c/busses/i2c-falcon.c @@ -0,0 +1,1040 @@ +/* + * Lantiq FALC(tm) ON - I2C bus adapter + * + * Parts based on i2c-designware.c and other i2c drivers from Linux 2.6.33 + * + * 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., 675 Mass Ave, Cambridge, MA 02139, USA. + * + * Copyright (C) 2010 Thomas Langer + */ + +/* + * CURRENT ISSUES: + * - no high speed support + * - supports only master mode + * - ten bit mode is not tested (no slave devices) + */ + +#include +#include +#include +#include +#include +#include +#include +#include +#include +#include +#include +#include +#include +#include + +#include + +/* I2C Identification Register */ +/* Module ID */ +#define I2C_ID_ID_MASK 0x0000FF00 +/* field offset */ +#define I2C_ID_ID_OFFSET 8 +/* Revision */ +#define I2C_ID_REV_MASK 0x000000FF +/* field offset */ +#define I2C_ID_REV_OFFSET 0 + +/* I2C Error Interrupt Request Source Status Register */ +/* TXF_OFL */ +#define I2C_ERR_IRQSS_TXF_OFL 0x00000008 +/* TXF_UFL */ +#define I2C_ERR_IRQSS_TXF_UFL 0x00000004 +/* RXF_OFL */ +#define I2C_ERR_IRQSS_RXF_OFL 0x00000002 +/* RXF_UFL */ +#define I2C_ERR_IRQSS_RXF_UFL 0x00000001 + +/* I2C Bus Status Register */ +/* Bus Status */ +#define I2C_BUS_STAT_BS_MASK 0x00000003 +/* I2C Bus is free. */ +#define I2C_BUS_STAT_BS_FREE 0x00000000 +/* + * The device is working as master and has claimed the control + * on the I2C-bus (busy master). + */ +#define I2C_BUS_STAT_BS_BM 0x00000002 + +/* I2C Interrupt Clear Register */ +/* Clear */ +#define I2C_ICR_BREQ_INT_CLR 0x00000008 +/* Clear */ +#define I2C_ICR_LBREQ_INT_CLR 0x00000004 + +/* I2C RUN Control Register */ +/* Enable */ +#define I2C_RUN_CTRL_RUN_EN 0x00000001 + +/* I2C Kernel Clock Control Register */ +/* field offset */ +#define I2C_CLC_RMC_OFFSET 8 +/* Enable */ +#define I2C_IMSC_I2C_P_INT_EN 0x00000020 +/* Enable */ +#define I2C_IMSC_I2C_ERR_INT_EN 0x00000010 +/* Enable */ +#define I2C_IMSC_BREQ_INT_EN 0x00000008 +/* Enable */ +#define I2C_IMSC_LBREQ_INT_EN 0x00000004 + +/* I2C Fractional Divider Configuration Register */ +/* field offset */ +#define I2C_FDIV_CFG_INC_OFFSET 16 +/* field offset */ +#define I2C_FDIV_CFG_DEC_OFFSET 0 + +/* I2C Fractional Divider (highspeed mode) Configuration Register */ +/* field offset */ +#define I2C_FDIV_HIGH_CFG_INC_OFFSET 16 +/* field offset */ +#define I2C_FDIV_HIGH_CFG_DEC_OFFSET 0 + +/* I2C Address Register */ +/* Enable */ +#define I2C_ADDR_CFG_SOPE_EN 0x00200000 +/* Enable */ +#define I2C_ADDR_CFG_SONA_EN 0x00100000 +/* Enable */ +#define I2C_ADDR_CFG_MnS_EN 0x00080000 + +/* I2C Protocol Interrupt Request Source Status Register */ +/* RX */ +#define I2C_P_IRQSS_RX 0x00000040 +/* TX_END */ +#define I2C_P_IRQSS_TX_END 0x00000020 +/* NACK */ +#define I2C_P_IRQSS_NACK 0x00000010 +/* AL */ +#define I2C_P_IRQSS_AL 0x00000008 + +/* I2C Raw Interrupt Status Register */ +/* Read: Interrupt occurred. */ +#define I2C_RIS_I2C_P_INT_INTOCC 0x00000020 +/* Read: Interrupt occurred. */ +#define I2C_RIS_I2C_ERR_INT_INTOCC 0x00000010 + +/* I2C End Data Control Register */ +/* + * Set End of Transmission - Note: Do not write '1' to this bit when bus is + * free. This will cause an abort after the first byte when a new transfer + * is started. + */ +#define I2C_ENDD_CTRL_SETEND 0x00000002 +/* TX FIFO Flow Control */ +#define I2C_FIFO_CFG_TXFC 0x00020000 +/* RX FIFO Flow Control */ +#define I2C_FIFO_CFG_RXFC 0x00010000 +/* Word aligned (character alignment of four characters) */ +#define I2C_FIFO_CFG_TXFA_TXFA2 0x00002000 +/* Word aligned (character alignment of four characters) */ +#define I2C_FIFO_CFG_RXFA_RXFA2 0x00000200 +/* 1 word */ +#define I2C_FIFO_CFG_TXBS_TXBS0 0x00000000 +/* 1 word */ +#define I2C_FIFO_CFG_RXBS_RXBS0 0x00000000 + + +/* I2C register structure */ +struct gpon_reg_i2c { + /* I2C Kernel Clock Control Register */ + unsigned int clc; /* 0x00000000 */ + /* Reserved */ + unsigned int res_0; /* 0x00000004 */ + /* I2C Identification Register */ + unsigned int id; /* 0x00000008 */ + /* Reserved */ + unsigned int res_1; /* 0x0000000C */ + /* + * I2C RUN Control Register - This register enables and disables the I2C + * peripheral. Before enabling, the I2C has to be configured properly. + * After enabling no configuration is possible + */ + unsigned int run_ctrl; /* 0x00000010 */ + /* + * I2C End Data Control Register - This register is used to either turn + * around the data transmission direction or to address another slave + * without sending a stop condition. Also the software can stop the + * slave-transmitter by sending a not-accolade when working as + * master-receiver or even stop data transmission immediately when + * operating as master-transmitter. The writing to the bits of this + * control register is only effective when in MASTER RECEIVES BYTES, + * MASTER TRANSMITS BYTES, MASTER RESTART or SLAVE RECEIVE BYTES state + */ + unsigned int endd_ctrl; /* 0x00000014 */ + /* + * I2C Fractional Divider Configuration Register - These register is + * used to program the fractional divider of the I2C bus. Before the + * peripheral is switched on by setting the RUN-bit the two (fixed) + * values for the two operating frequencies are programmed into these + * (configuration) registers. The Register FDIV_HIGH_CFG has the same + * layout as I2C_FDIV_CFG. + */ + unsigned int fdiv_cfg; /* 0x00000018 */ + /* + * I2C Fractional Divider (highspeed mode) Configuration Register + * These register is used to program the fractional divider of the I2C + * bus. Before the peripheral is switched on by setting the RUN-bit the + * two (fixed) values for the two operating frequencies are programmed + * into these (configuration) registers. The Register FDIV_CFG has the + * same layout as I2C_FDIV_CFG. + */ + unsigned int fdiv_high_cfg; /* 0x0000001C */ + /* I2C Address Configuration Register */ + unsigned int addr_cfg; /* 0x00000020 */ + /* + * I2C Bus Status Register - This register gives a status information + * of the I2C. This additional information can be used by the software + * to start proper actions. + */ + unsigned int bus_stat; /* 0x00000024 */ + /* I2C FIFO Configuration Register */ + unsigned int fifo_cfg; /* 0x00000028 */ + /* I2C Maximum Received Packet Size Register */ + unsigned int mrps_ctrl; /* 0x0000002C */ + /* I2C Received Packet Size Status Register */ + unsigned int rps_stat; /* 0x00000030 */ + /* I2C Transmit Packet Size Register */ + unsigned int tps_ctrl; /* 0x00000034 */ + /* I2C Filled FIFO Stages Status Register */ + unsigned int ffs_stat; /* 0x00000038 */ + /* Reserved */ + unsigned int res_2; /* 0x0000003C */ + /* I2C Timing Configuration Register */ + unsigned int tim_cfg; /* 0x00000040 */ + /* Reserved */ + unsigned int res_3[7]; /* 0x00000044 */ + /* I2C Error Interrupt Request Source Mask Register */ + unsigned int err_irqsm; /* 0x00000060 */ + /* I2C Error Interrupt Request Source Status Register */ + unsigned int err_irqss; /* 0x00000064 */ + /* I2C Error Interrupt Request Source Clear Register */ + unsigned int err_irqsc; /* 0x00000068 */ + /* Reserved */ + unsigned int res_4; /* 0x0000006C */ + /* I2C Protocol Interrupt Request Source Mask Register */ + unsigned int p_irqsm; /* 0x00000070 */ + /* I2C Protocol Interrupt Request Source Status Register */ + unsigned int p_irqss; /* 0x00000074 */ + /* I2C Protocol Interrupt Request Source Clear Register */ + unsigned int p_irqsc; /* 0x00000078 */ + /* Reserved */ + unsigned int res_5; /* 0x0000007C */ + /* I2C Raw Interrupt Status Register */ + unsigned int ris; /* 0x00000080 */ + /* I2C Interrupt Mask Control Register */ + unsigned int imsc; /* 0x00000084 */ + /* I2C Masked Interrupt Status Register */ + unsigned int mis; /* 0x00000088 */ + /* I2C Interrupt Clear Register */ + unsigned int icr; /* 0x0000008C */ + /* I2C Interrupt Set Register */ + unsigned int isr; /* 0x00000090 */ + /* I2C DMA Enable Register */ + unsigned int dmae; /* 0x00000094 */ + /* Reserved */ + unsigned int res_6[8154]; /* 0x00000098 */ + /* I2C Transmit Data Register */ + unsigned int txd; /* 0x00008000 */ + /* Reserved */ + unsigned int res_7[4095]; /* 0x00008004 */ + /* I2C Receive Data Register */ + unsigned int rxd; /* 0x0000C000 */ + /* Reserved */ + unsigned int res_8[4095]; /* 0x0000C004 */ +}; + +/* mapping for access macros */ +#define i2c ((struct gpon_reg_i2c *)priv->membase) +#define reg_r32(reg) __raw_readl(reg) +#define reg_w32(val, reg) __raw_writel(val, reg) +#define reg_w32_mask(clear, set, reg) \ + reg_w32((reg_r32(reg) & ~(clear)) | (set), reg) +#define reg_r32_table(reg, idx) reg_r32(&((uint32_t *)®)[idx]) +#define reg_w32_table(val, reg, idx) reg_w32(val, &((uint32_t *)®)[idx]) + +#define i2c_r32(reg) reg_r32(&i2c->reg) +#define i2c_w32(val, reg) reg_w32(val, &i2c->reg) +#define i2c_w32_mask(clear, set, reg) reg_w32_mask(clear, set, &i2c->reg) + +#define DRV_NAME "i2c-falcon" +#define DRV_VERSION "1.01" + +#define FALCON_I2C_BUSY_TIMEOUT 20 /* ms */ + +#ifdef DEBUG +#define FALCON_I2C_XFER_TIMEOUT (25 * HZ) +#else +#define FALCON_I2C_XFER_TIMEOUT HZ +#endif +#if defined(DEBUG) && 0 +#define PRINTK(arg...) pr_info(arg) +#else +#define PRINTK(arg...) do {} while (0) +#endif + +#define FALCON_I2C_IMSC_DEFAULT_MASK (I2C_IMSC_I2C_P_INT_EN | \ + I2C_IMSC_I2C_ERR_INT_EN) + +#define FALCON_I2C_ARB_LOST (1 << 0) +#define FALCON_I2C_NACK (1 << 1) +#define FALCON_I2C_RX_UFL (1 << 2) +#define FALCON_I2C_RX_OFL (1 << 3) +#define FALCON_I2C_TX_UFL (1 << 4) +#define FALCON_I2C_TX_OFL (1 << 5) + +struct falcon_i2c { + struct mutex mutex; + + enum { + FALCON_I2C_MODE_100 = 1, + FALCON_I2C_MODE_400 = 2, + FALCON_I2C_MODE_3400 = 3 + } mode; /* current speed mode */ + + struct clk *clk; /* clock input for i2c hardware block */ + struct gpon_reg_i2c __iomem *membase; /* base of mapped registers */ + int irq_lb, irq_b, irq_err, irq_p; /* last burst, burst, error, + protocol IRQs */ + + struct i2c_adapter adap; + struct device *dev; + + struct completion cmd_complete; + + /* message transfer data */ + /* current message */ + struct i2c_msg *current_msg; + /* number of messages to handle */ + int msgs_num; + /* current buffer */ + u8 *msg_buf; + /* remaining length of current buffer */ + u32 msg_buf_len; + /* error status of the current transfer */ + int msg_err; + + /* master status codes */ + enum { + STATUS_IDLE, + STATUS_ADDR, /* address phase */ + STATUS_WRITE, + STATUS_READ, + STATUS_READ_END, + STATUS_STOP + } status; +}; + +static irqreturn_t falcon_i2c_isr(int irq, void *dev_id); + +static inline void enable_burst_irq(struct falcon_i2c *priv) +{ + i2c_w32_mask(0, I2C_IMSC_LBREQ_INT_EN | I2C_IMSC_BREQ_INT_EN, imsc); +} +static inline void disable_burst_irq(struct falcon_i2c *priv) +{ + i2c_w32_mask(I2C_IMSC_LBREQ_INT_EN | I2C_IMSC_BREQ_INT_EN, 0, imsc); +} + +static void prepare_msg_send_addr(struct falcon_i2c *priv) +{ + struct i2c_msg *msg = priv->current_msg; + int rd = !!(msg->flags & I2C_M_RD); + u16 addr = msg->addr; + + /* new i2c_msg */ + priv->msg_buf = msg->buf; + priv->msg_buf_len = msg->len; + if (rd) + priv->status = STATUS_READ; + else + priv->status = STATUS_WRITE; + + /* send slave address */ + if (msg->flags & I2C_M_TEN) { + i2c_w32(0xf0 | ((addr & 0x300) >> 7) | rd, txd); + i2c_w32(addr & 0xff, txd); + } else + i2c_w32((addr & 0x7f) << 1 | rd, txd); +} + +static void set_tx_len(struct falcon_i2c *priv) +{ + struct i2c_msg *msg = priv->current_msg; + int len = (msg->flags & I2C_M_TEN) ? 2 : 1; + + PRINTK("set_tx_len %cX\n", (msg->flags & I2C_M_RD) ? ('R') : ('T')); + + priv->status = STATUS_ADDR; + + if (!(msg->flags & I2C_M_RD)) { + len += msg->len; + } else { + /* set maximum received packet size (before rx int!) */ + i2c_w32(msg->len, mrps_ctrl); + } + i2c_w32(len, tps_ctrl); + enable_burst_irq(priv); +} + +static int falcon_i2c_hw_init(struct i2c_adapter *adap) +{ + struct falcon_i2c *priv = i2c_get_adapdata(adap); + + /* disable bus */ + i2c_w32_mask(I2C_RUN_CTRL_RUN_EN, 0, run_ctrl); + +#ifndef DEBUG + /* set normal operation clock divider */ + i2c_w32(1 << I2C_CLC_RMC_OFFSET, clc); +#else + /* for debugging a higher divider value! */ + i2c_w32(0xF0 << I2C_CLC_RMC_OFFSET, clc); +#endif + + /* set frequency */ + if (priv->mode == FALCON_I2C_MODE_100) { + dev_dbg(priv->dev, "set standard mode (100 kHz)\n"); + i2c_w32(0, fdiv_high_cfg); + i2c_w32((1 << I2C_FDIV_CFG_INC_OFFSET) | + (499 << I2C_FDIV_CFG_DEC_OFFSET), + fdiv_cfg); + } else if (priv->mode == FALCON_I2C_MODE_400) { + dev_dbg(priv->dev, "set fast mode (400 kHz)\n"); + i2c_w32(0, fdiv_high_cfg); + i2c_w32((1 << I2C_FDIV_CFG_INC_OFFSET) | + (124 << I2C_FDIV_CFG_DEC_OFFSET), + fdiv_cfg); + } else if (priv->mode == FALCON_I2C_MODE_3400) { + dev_dbg(priv->dev, "set high mode (3.4 MHz)\n"); + i2c_w32(0, fdiv_cfg); + /* TODO recalculate value for 100MHz input */ + i2c_w32((41 << I2C_FDIV_HIGH_CFG_INC_OFFSET) | + (152 << I2C_FDIV_HIGH_CFG_DEC_OFFSET), + fdiv_high_cfg); + } else { + dev_warn(priv->dev, "unknown mode\n"); + return -ENODEV; + } + + /* configure fifo */ + i2c_w32(I2C_FIFO_CFG_TXFC | /* tx fifo as flow controller */ + I2C_FIFO_CFG_RXFC | /* rx fifo as flow controller */ + I2C_FIFO_CFG_TXFA_TXFA2 | /* tx fifo 4-byte aligned */ + I2C_FIFO_CFG_RXFA_RXFA2 | /* rx fifo 4-byte aligned */ + I2C_FIFO_CFG_TXBS_TXBS0 | /* tx fifo burst size is 1 word */ + I2C_FIFO_CFG_RXBS_RXBS0, /* rx fifo burst size is 1 word */ + fifo_cfg); + + /* configure address */ + i2c_w32(I2C_ADDR_CFG_SOPE_EN | /* generate stop when no more data + in the fifo */ + I2C_ADDR_CFG_SONA_EN | /* generate stop when NA received */ + I2C_ADDR_CFG_MnS_EN | /* we are master device */ + 0, /* our slave address (not used!) */ + addr_cfg); + + /* enable bus */ + i2c_w32_mask(0, I2C_RUN_CTRL_RUN_EN, run_ctrl); + + return 0; +} + +static int falcon_i2c_wait_bus_not_busy(struct falcon_i2c *priv) +{ + int timeout = FALCON_I2C_BUSY_TIMEOUT; + + while ((i2c_r32(bus_stat) & I2C_BUS_STAT_BS_MASK) + != I2C_BUS_STAT_BS_FREE) { + if (timeout <= 0) { + dev_warn(priv->dev, "timeout waiting for bus ready\n"); + return -ETIMEDOUT; + } + timeout--; + mdelay(1); + } + + return 0; +} + +static void falcon_i2c_tx(struct falcon_i2c *priv, int last) +{ + if (priv->msg_buf_len && priv->msg_buf) { + i2c_w32(*priv->msg_buf, txd); + + if (--priv->msg_buf_len) + priv->msg_buf++; + else + priv->msg_buf = NULL; + } else + last = 1; + + if (last) + disable_burst_irq(priv); +} + +static void falcon_i2c_rx(struct falcon_i2c *priv, int last) +{ + u32 fifo_stat, timeout; + if (priv->msg_buf_len && priv->msg_buf) { + timeout = 5000000; + do { + fifo_stat = i2c_r32(ffs_stat); + } while (!fifo_stat && --timeout); + if (!timeout) { + last = 1; + PRINTK("\nrx timeout\n"); + goto err; + } + while (fifo_stat) { + *priv->msg_buf = i2c_r32(rxd); + if (--priv->msg_buf_len) + priv->msg_buf++; + else { + priv->msg_buf = NULL; + last = 1; + break; + } + #if 0 + fifo_stat = i2c_r32(ffs_stat); + #else + /* do not read more than burst size, otherwise no "last + burst" is generated and the transaction is blocked! */ + fifo_stat = 0; + #endif + } + } else { + last = 1; + } +err: + if (last) { + disable_burst_irq(priv); + + if (priv->status == STATUS_READ_END) { + /* do the STATUS_STOP and complete() here, as sometimes + the tx_end is already seen before this is finished */ + priv->status = STATUS_STOP; + complete(&priv->cmd_complete); + } else { + i2c_w32(I2C_ENDD_CTRL_SETEND, endd_ctrl); + priv->status = STATUS_READ_END; + } + } +} + +static void falcon_i2c_xfer_init(struct falcon_i2c *priv) +{ + /* enable interrupts */ + i2c_w32(FALCON_I2C_IMSC_DEFAULT_MASK, imsc); + + /* trigger transfer of first msg */ + set_tx_len(priv); +} + +static void dump_msgs(struct i2c_msg msgs[], int num, int rx) +{ +#if defined(DEBUG) + int i, j; + pr_info("Messages %d %s\n", num, rx ? "out" : "in"); + for (i = 0; i < num; i++) { + pr_info("%2d %cX Msg(%d) addr=0x%X: ", i, + (msgs[i].flags & I2C_M_RD) ? ('R') : ('T'), + msgs[i].len, msgs[i].addr); + if (!(msgs[i].flags & I2C_M_RD) || rx) { + for (j = 0; j < msgs[i].len; j++) + printk("%02X ", msgs[i].buf[j]); + } + printk("\n"); + } +#endif +} + +static void falcon_i2c_release_bus(struct falcon_i2c *priv) +{ + if ((i2c_r32(bus_stat) & I2C_BUS_STAT_BS_MASK) == I2C_BUS_STAT_BS_BM) + i2c_w32(I2C_ENDD_CTRL_SETEND, endd_ctrl); +} + +static int falcon_i2c_xfer(struct i2c_adapter *adap, struct i2c_msg msgs[], + int num) +{ + struct falcon_i2c *priv = i2c_get_adapdata(adap); + int ret; + + dev_dbg(priv->dev, "xfer %u messages\n", num); + dump_msgs(msgs, num, 0); + + mutex_lock(&priv->mutex); + + INIT_COMPLETION(priv->cmd_complete); + priv->current_msg = msgs; + priv->msgs_num = num; + priv->msg_err = 0; + priv->status = STATUS_IDLE; + + /* wait for the bus to become ready */ + ret = falcon_i2c_wait_bus_not_busy(priv); + if (ret) + goto done; + + while (priv->msgs_num) { + /* start the transfers */ + falcon_i2c_xfer_init(priv); + + /* wait for transfers to complete */ + ret = wait_for_completion_interruptible_timeout( + &priv->cmd_complete, FALCON_I2C_XFER_TIMEOUT); + if (ret == 0) { + dev_err(priv->dev, "controller timed out\n"); + falcon_i2c_hw_init(adap); + ret = -ETIMEDOUT; + goto done; + } else if (ret < 0) + goto done; + + if (priv->msg_err) { + if (priv->msg_err & FALCON_I2C_NACK) + ret = -ENXIO; + else + ret = -EREMOTEIO; + goto done; + } + if (--priv->msgs_num) + priv->current_msg++; + } + /* no error? */ + ret = num; + +done: + falcon_i2c_release_bus(priv); + + mutex_unlock(&priv->mutex); + + if (ret >= 0) + dump_msgs(msgs, num, 1); + + PRINTK("XFER ret %d\n", ret); + return ret; +} + +static irqreturn_t falcon_i2c_isr_burst(int irq, void *dev_id) +{ + struct falcon_i2c *priv = dev_id; + struct i2c_msg *msg = priv->current_msg; + int last = (irq == priv->irq_lb); + + if (last) + PRINTK("LB "); + else + PRINTK("B "); + + if (msg->flags & I2C_M_RD) { + switch (priv->status) { + case STATUS_ADDR: + PRINTK("X"); + prepare_msg_send_addr(priv); + disable_burst_irq(priv); + break; + case STATUS_READ: + case STATUS_READ_END: + PRINTK("R"); + falcon_i2c_rx(priv, last); + break; + default: + disable_burst_irq(priv); + PRINTK("Status R %d\n", priv->status); + break; + } + } else { + switch (priv->status) { + case STATUS_ADDR: + PRINTK("x"); + prepare_msg_send_addr(priv); + break; + case STATUS_WRITE: + PRINTK("w"); + falcon_i2c_tx(priv, last); + break; + default: + disable_burst_irq(priv); + PRINTK("Status W %d\n", priv->status); + break; + } + } + + i2c_w32(I2C_ICR_BREQ_INT_CLR | I2C_ICR_LBREQ_INT_CLR, icr); + return IRQ_HANDLED; +} + +static void falcon_i2c_isr_prot(struct falcon_i2c *priv) +{ + u32 i_pro = i2c_r32(p_irqss); + + PRINTK("i2c-p"); + + /* not acknowledge */ + if (i_pro & I2C_P_IRQSS_NACK) { + priv->msg_err |= FALCON_I2C_NACK; + PRINTK(" nack"); + } + + /* arbitration lost */ + if (i_pro & I2C_P_IRQSS_AL) { + priv->msg_err |= FALCON_I2C_ARB_LOST; + PRINTK(" arb-lost"); + } + /* tx -> rx switch */ + if (i_pro & I2C_P_IRQSS_RX) + PRINTK(" rx"); + + /* tx end */ + if (i_pro & I2C_P_IRQSS_TX_END) + PRINTK(" txend"); + PRINTK("\n"); + + if (!priv->msg_err) { + /* tx -> rx switch */ + if (i_pro & I2C_P_IRQSS_RX) { + priv->status = STATUS_READ; + enable_burst_irq(priv); + } + if (i_pro & I2C_P_IRQSS_TX_END) { + if (priv->status == STATUS_READ) + priv->status = STATUS_READ_END; + else { + disable_burst_irq(priv); + priv->status = STATUS_STOP; + } + } + } + + i2c_w32(i_pro, p_irqsc); +} + +static irqreturn_t falcon_i2c_isr(int irq, void *dev_id) +{ + u32 i_raw, i_err = 0; + struct falcon_i2c *priv = dev_id; + + i_raw = i2c_r32(mis); + PRINTK("i_raw 0x%08X\n", i_raw); + + /* error interrupt */ + if (i_raw & I2C_RIS_I2C_ERR_INT_INTOCC) { + i_err = i2c_r32(err_irqss); + PRINTK("i_err 0x%08X bus_stat 0x%04X\n", + i_err, i2c_r32(bus_stat)); + + /* tx fifo overflow (8) */ + if (i_err & I2C_ERR_IRQSS_TXF_OFL) + priv->msg_err |= FALCON_I2C_TX_OFL; + + /* tx fifo underflow (4) */ + if (i_err & I2C_ERR_IRQSS_TXF_UFL) + priv->msg_err |= FALCON_I2C_TX_UFL; + + /* rx fifo overflow (2) */ + if (i_err & I2C_ERR_IRQSS_RXF_OFL) + priv->msg_err |= FALCON_I2C_RX_OFL; + + /* rx fifo underflow (1) */ + if (i_err & I2C_ERR_IRQSS_RXF_UFL) + priv->msg_err |= FALCON_I2C_RX_UFL; + + i2c_w32(i_err, err_irqsc); + } + + /* protocol interrupt */ + if (i_raw & I2C_RIS_I2C_P_INT_INTOCC) + falcon_i2c_isr_prot(priv); + + if ((priv->msg_err) || (priv->status == STATUS_STOP)) + complete(&priv->cmd_complete); + + return IRQ_HANDLED; +} + +static u32 falcon_i2c_functionality(struct i2c_adapter *adap) +{ + return I2C_FUNC_I2C | + I2C_FUNC_10BIT_ADDR | + I2C_FUNC_SMBUS_EMUL; +} + +static struct i2c_algorithm falcon_i2c_algorithm = { + .master_xfer = falcon_i2c_xfer, + .functionality = falcon_i2c_functionality, +}; + +static int __devinit falcon_i2c_probe(struct platform_device *pdev) +{ + int ret = 0; + struct falcon_i2c *priv; + struct i2c_adapter *adap; + struct resource *mmres, *ioarea, + *irqres_lb, *irqres_b, *irqres_err, *irqres_p; + struct clk *clk; + + dev_dbg(&pdev->dev, "probing\n"); + + mmres = platform_get_resource(pdev, IORESOURCE_MEM, 0); + irqres_lb = platform_get_resource_byname(pdev, IORESOURCE_IRQ, + "i2c_lb"); + irqres_b = platform_get_resource_byname(pdev, IORESOURCE_IRQ, "i2c_b"); + irqres_err = platform_get_resource_byname(pdev, IORESOURCE_IRQ, + "i2c_err"); + irqres_p = platform_get_resource_byname(pdev, IORESOURCE_IRQ, "i2c_p"); + + if (!mmres || !irqres_lb || !irqres_b || !irqres_err || !irqres_p) { + dev_err(&pdev->dev, "no resources\n"); + return -ENODEV; + } + + clk = clk_get_fpi(); + if (IS_ERR(clk)) { + dev_err(&pdev->dev, "failed to get fpi clk\n"); + return -ENOENT; + } + + if (clk_get_rate(clk) != 100000000) { + dev_err(&pdev->dev, "input clock is not 100MHz\n"); + return -ENOENT; + } + clk = clk_get(&pdev->dev, NULL); + if (IS_ERR(clk)) { + dev_err(&pdev->dev, "failed to get i2c clk\n"); + return -ENOENT; + } + + /* allocate private data */ + priv = kzalloc(sizeof(*priv), GFP_KERNEL); + if (!priv) { + dev_err(&pdev->dev, "can't allocate private data\n"); + return -ENOMEM; + } + + adap = &priv->adap; + i2c_set_adapdata(adap, priv); + adap->owner = THIS_MODULE; + adap->class = I2C_CLASS_HWMON | I2C_CLASS_SPD; + strlcpy(adap->name, DRV_NAME "-adapter", sizeof(adap->name)); + adap->algo = &falcon_i2c_algorithm; + + priv->mode = FALCON_I2C_MODE_100; + priv->clk = clk; + priv->dev = &pdev->dev; + + init_completion(&priv->cmd_complete); + mutex_init(&priv->mutex); + + if (ltq_gpio_request(&pdev->dev, 107, 0, 0, DRV_NAME":sda") || + ltq_gpio_request(&pdev->dev, 108, 0, 0, DRV_NAME":scl")) + { + dev_err(&pdev->dev, "I2C gpios not available\n"); + ret = -ENXIO; + goto err_free_priv; + } + + ioarea = request_mem_region(mmres->start, resource_size(mmres), + pdev->name); + + if (ioarea == NULL) { + dev_err(&pdev->dev, "I2C region already claimed\n"); + ret = -ENXIO; + goto err_free_gpio; + } + + /* map memory */ + priv->membase = ioremap_nocache(mmres->start & ~KSEG1, + resource_size(mmres)); + if (priv->membase == NULL) { + ret = -ENOMEM; + goto err_release_region; + } + + priv->irq_lb = irqres_lb->start; + ret = request_irq(priv->irq_lb, falcon_i2c_isr_burst, IRQF_DISABLED, + irqres_lb->name, priv); + if (ret) { + dev_err(&pdev->dev, "can't get last burst IRQ %d\n", + irqres_lb->start); + ret = -ENODEV; + goto err_unmap_mem; + } + + priv->irq_b = irqres_b->start; + ret = request_irq(priv->irq_b, falcon_i2c_isr_burst, IRQF_DISABLED, + irqres_b->name, priv); + if (ret) { + dev_err(&pdev->dev, "can't get burst IRQ %d\n", + irqres_b->start); + ret = -ENODEV; + goto err_free_lb_irq; + } + + priv->irq_err = irqres_err->start; + ret = request_irq(priv->irq_err, falcon_i2c_isr, IRQF_DISABLED, + irqres_err->name, priv); + if (ret) { + dev_err(&pdev->dev, "can't get error IRQ %d\n", + irqres_err->start); + ret = -ENODEV; + goto err_free_b_irq; + } + + priv->irq_p = irqres_p->start; + ret = request_irq(priv->irq_p, falcon_i2c_isr, IRQF_DISABLED, + irqres_p->name, priv); + if (ret) { + dev_err(&pdev->dev, "can't get protocol IRQ %d\n", + irqres_p->start); + ret = -ENODEV; + goto err_free_err_irq; + } + + dev_dbg(&pdev->dev, "mapped io-space to %p\n", priv->membase); + dev_dbg(&pdev->dev, "use IRQs %d, %d, %d, %d\n", irqres_lb->start, + irqres_b->start, irqres_err->start, irqres_p->start); + + /* add our adapter to the i2c stack */ + ret = i2c_add_numbered_adapter(adap); + if (ret) { + dev_err(&pdev->dev, "can't register I2C adapter\n"); + goto err_free_p_irq; + } + + platform_set_drvdata(pdev, priv); + i2c_set_adapdata(adap, priv); + + /* print module version information */ + dev_dbg(&pdev->dev, "module id=%u revision=%u\n", + (i2c_r32(id) & I2C_ID_ID_MASK) >> I2C_ID_ID_OFFSET, + (i2c_r32(id) & I2C_ID_REV_MASK) >> I2C_ID_REV_OFFSET); + + /* initialize HW */ + ret = falcon_i2c_hw_init(adap); + if (ret) { + dev_err(&pdev->dev, "can't configure adapter\n"); + goto err_remove_adapter; + } + + dev_info(&pdev->dev, "version %s\n", DRV_VERSION); + + return 0; + +err_remove_adapter: + i2c_del_adapter(adap); + platform_set_drvdata(pdev, NULL); + +err_free_p_irq: + free_irq(priv->irq_p, priv); + +err_free_err_irq: + free_irq(priv->irq_err, priv); + +err_free_b_irq: + free_irq(priv->irq_b, priv); + +err_free_lb_irq: + free_irq(priv->irq_lb, priv); + +err_unmap_mem: + iounmap(priv->membase); + +err_release_region: + release_mem_region(mmres->start, resource_size(mmres)); + +err_free_gpio: + gpio_free(108); + gpio_free(107); + +err_free_priv: + kfree(priv); + + return ret; +} + +static int __devexit falcon_i2c_remove(struct platform_device *pdev) +{ + struct falcon_i2c *priv = platform_get_drvdata(pdev); + struct resource *mmres; + + /* disable bus */ + i2c_w32_mask(I2C_RUN_CTRL_RUN_EN, 0, run_ctrl); + + /* remove driver */ + platform_set_drvdata(pdev, NULL); + i2c_del_adapter(&priv->adap); + + free_irq(priv->irq_lb, priv); + free_irq(priv->irq_b, priv); + free_irq(priv->irq_err, priv); + free_irq(priv->irq_p, priv); + + iounmap(priv->membase); + + gpio_free(108); + gpio_free(107); + + kfree(priv); + + mmres = platform_get_resource(pdev, IORESOURCE_MEM, 0); + release_mem_region(mmres->start, resource_size(mmres)); + + dev_dbg(&pdev->dev, "removed\n"); + + return 0; +} + +static struct platform_driver falcon_i2c_driver = { + .probe = falcon_i2c_probe, + .remove = __devexit_p(falcon_i2c_remove), + .driver = { + .name = DRV_NAME, + .owner = THIS_MODULE, + }, +}; + +static int __init falcon_i2c_init(void) +{ + int ret; + + ret = platform_driver_register(&falcon_i2c_driver); + + if (ret) + pr_debug(DRV_NAME ": can't register platform driver\n"); + + return ret; +} + +static void __exit falcon_i2c_exit(void) +{ + platform_driver_unregister(&falcon_i2c_driver); +} + +module_init(falcon_i2c_init); +module_exit(falcon_i2c_exit); + +MODULE_DESCRIPTION("Lantiq FALC(tm) ON - I2C bus adapter"); +MODULE_ALIAS("platform:" DRV_NAME); +MODULE_LICENSE("GPL"); +MODULE_VERSION(DRV_VERSION);