diff options
Diffstat (limited to 'drivers/i2c/busses/i2c-mv64xxx.c')
-rw-r--r-- | drivers/i2c/busses/i2c-mv64xxx.c | 321 |
1 files changed, 161 insertions, 160 deletions
diff --git a/drivers/i2c/busses/i2c-mv64xxx.c b/drivers/i2c/busses/i2c-mv64xxx.c index 1a3abd6a0bf..b1f42bf4096 100644 --- a/drivers/i2c/busses/i2c-mv64xxx.c +++ b/drivers/i2c/busses/i2c-mv64xxx.c @@ -19,19 +19,15 @@ #include <linux/platform_device.h> #include <linux/io.h> #include <linux/of.h> +#include <linux/of_device.h> #include <linux/of_irq.h> #include <linux/of_i2c.h> #include <linux/clk.h> #include <linux/err.h> -/* Register defines */ -#define MV64XXX_I2C_REG_SLAVE_ADDR 0x00 -#define MV64XXX_I2C_REG_DATA 0x04 -#define MV64XXX_I2C_REG_CONTROL 0x08 -#define MV64XXX_I2C_REG_STATUS 0x0c -#define MV64XXX_I2C_REG_BAUD 0x0c -#define MV64XXX_I2C_REG_EXT_SLAVE_ADDR 0x10 -#define MV64XXX_I2C_REG_SOFT_RESET 0x1c +#define MV64XXX_I2C_ADDR_ADDR(val) ((val & 0x7f) << 1) +#define MV64XXX_I2C_BAUD_DIV_N(val) (val & 0x7) +#define MV64XXX_I2C_BAUD_DIV_M(val) ((val & 0xf) << 3) #define MV64XXX_I2C_REG_CONTROL_ACK 0x00000004 #define MV64XXX_I2C_REG_CONTROL_IFLG 0x00000008 @@ -85,15 +81,26 @@ enum { MV64XXX_I2C_ACTION_SEND_STOP, }; +struct mv64xxx_i2c_regs { + u8 addr; + u8 ext_addr; + u8 data; + u8 control; + u8 status; + u8 clock; + u8 soft_reset; +}; + struct mv64xxx_i2c_data { + struct i2c_msg *msgs; + int num_msgs; int irq; u32 state; u32 action; u32 aborting; u32 cntl_bits; void __iomem *reg_base; - u32 reg_base_p; - u32 reg_size; + struct mv64xxx_i2c_regs reg_offsets; u32 addr1; u32 addr2; u32 bytes_left; @@ -112,6 +119,52 @@ struct mv64xxx_i2c_data { struct i2c_adapter adapter; }; +static struct mv64xxx_i2c_regs mv64xxx_i2c_regs_mv64xxx = { + .addr = 0x00, + .ext_addr = 0x10, + .data = 0x04, + .control = 0x08, + .status = 0x0c, + .clock = 0x0c, + .soft_reset = 0x1c, +}; + +static struct mv64xxx_i2c_regs mv64xxx_i2c_regs_sun4i = { + .addr = 0x00, + .ext_addr = 0x04, + .data = 0x08, + .control = 0x0c, + .status = 0x10, + .clock = 0x14, + .soft_reset = 0x18, +}; + +static void +mv64xxx_i2c_prepare_for_io(struct mv64xxx_i2c_data *drv_data, + struct i2c_msg *msg) +{ + u32 dir = 0; + + drv_data->msg = msg; + drv_data->byte_posn = 0; + drv_data->bytes_left = msg->len; + drv_data->aborting = 0; + drv_data->rc = 0; + drv_data->cntl_bits = MV64XXX_I2C_REG_CONTROL_ACK | + MV64XXX_I2C_REG_CONTROL_INTEN | MV64XXX_I2C_REG_CONTROL_TWSIEN; + + if (msg->flags & I2C_M_RD) + dir = 1; + + if (msg->flags & I2C_M_TEN) { + drv_data->addr1 = 0xf0 | (((u32)msg->addr & 0x300) >> 7) | dir; + drv_data->addr2 = (u32)msg->addr & 0xff; + } else { + drv_data->addr1 = MV64XXX_I2C_ADDR_ADDR((u32)msg->addr) | dir; + drv_data->addr2 = 0; + } +} + /* ***************************************************************************** * @@ -124,13 +177,13 @@ struct mv64xxx_i2c_data { static void mv64xxx_i2c_hw_init(struct mv64xxx_i2c_data *drv_data) { - writel(0, drv_data->reg_base + MV64XXX_I2C_REG_SOFT_RESET); - writel((((drv_data->freq_m & 0xf) << 3) | (drv_data->freq_n & 0x7)), - drv_data->reg_base + MV64XXX_I2C_REG_BAUD); - writel(0, drv_data->reg_base + MV64XXX_I2C_REG_SLAVE_ADDR); - writel(0, drv_data->reg_base + MV64XXX_I2C_REG_EXT_SLAVE_ADDR); + writel(0, drv_data->reg_base + drv_data->reg_offsets.soft_reset); + writel(MV64XXX_I2C_BAUD_DIV_M(drv_data->freq_m) | MV64XXX_I2C_BAUD_DIV_N(drv_data->freq_n), + drv_data->reg_base + drv_data->reg_offsets.clock); + writel(0, drv_data->reg_base + drv_data->reg_offsets.addr); + writel(0, drv_data->reg_base + drv_data->reg_offsets.ext_addr); writel(MV64XXX_I2C_REG_CONTROL_TWSIEN | MV64XXX_I2C_REG_CONTROL_STOP, - drv_data->reg_base + MV64XXX_I2C_REG_CONTROL); + drv_data->reg_base + drv_data->reg_offsets.control); drv_data->state = MV64XXX_I2C_STATE_IDLE; } @@ -170,7 +223,7 @@ mv64xxx_i2c_fsm(struct mv64xxx_i2c_data *drv_data, u32 status) if ((drv_data->bytes_left == 0) || (drv_data->aborting && (drv_data->byte_posn != 0))) { - if (drv_data->send_stop) { + if (drv_data->send_stop || drv_data->aborting) { drv_data->action = MV64XXX_I2C_ACTION_SEND_STOP; drv_data->state = MV64XXX_I2C_STATE_IDLE; } else { @@ -227,7 +280,7 @@ mv64xxx_i2c_fsm(struct mv64xxx_i2c_data *drv_data, u32 status) /* Doesn't seem to be a device at other end */ drv_data->action = MV64XXX_I2C_ACTION_SEND_STOP; drv_data->state = MV64XXX_I2C_STATE_IDLE; - drv_data->rc = -ENODEV; + drv_data->rc = -ENXIO; break; default: @@ -247,58 +300,71 @@ mv64xxx_i2c_do_action(struct mv64xxx_i2c_data *drv_data) { switch(drv_data->action) { case MV64XXX_I2C_ACTION_SEND_RESTART: + /* We should only get here if we have further messages */ + BUG_ON(drv_data->num_msgs == 0); + drv_data->cntl_bits |= MV64XXX_I2C_REG_CONTROL_START; - drv_data->cntl_bits &= ~MV64XXX_I2C_REG_CONTROL_INTEN; writel(drv_data->cntl_bits, - drv_data->reg_base + MV64XXX_I2C_REG_CONTROL); - drv_data->block = 0; - wake_up(&drv_data->waitq); + drv_data->reg_base + drv_data->reg_offsets.control); + + drv_data->msgs++; + drv_data->num_msgs--; + + /* Setup for the next message */ + mv64xxx_i2c_prepare_for_io(drv_data, drv_data->msgs); + + /* + * We're never at the start of the message here, and by this + * time it's already too late to do any protocol mangling. + * Thankfully, do not advertise support for that feature. + */ + drv_data->send_stop = drv_data->num_msgs == 1; break; case MV64XXX_I2C_ACTION_CONTINUE: writel(drv_data->cntl_bits, - drv_data->reg_base + MV64XXX_I2C_REG_CONTROL); + drv_data->reg_base + drv_data->reg_offsets.control); break; case MV64XXX_I2C_ACTION_SEND_START: writel(drv_data->cntl_bits | MV64XXX_I2C_REG_CONTROL_START, - drv_data->reg_base + MV64XXX_I2C_REG_CONTROL); + drv_data->reg_base + drv_data->reg_offsets.control); break; case MV64XXX_I2C_ACTION_SEND_ADDR_1: writel(drv_data->addr1, - drv_data->reg_base + MV64XXX_I2C_REG_DATA); + drv_data->reg_base + drv_data->reg_offsets.data); writel(drv_data->cntl_bits, - drv_data->reg_base + MV64XXX_I2C_REG_CONTROL); + drv_data->reg_base + drv_data->reg_offsets.control); break; case MV64XXX_I2C_ACTION_SEND_ADDR_2: writel(drv_data->addr2, - drv_data->reg_base + MV64XXX_I2C_REG_DATA); + drv_data->reg_base + drv_data->reg_offsets.data); writel(drv_data->cntl_bits, - drv_data->reg_base + MV64XXX_I2C_REG_CONTROL); + drv_data->reg_base + drv_data->reg_offsets.control); break; case MV64XXX_I2C_ACTION_SEND_DATA: writel(drv_data->msg->buf[drv_data->byte_posn++], - drv_data->reg_base + MV64XXX_I2C_REG_DATA); + drv_data->reg_base + drv_data->reg_offsets.data); writel(drv_data->cntl_bits, - drv_data->reg_base + MV64XXX_I2C_REG_CONTROL); + drv_data->reg_base + drv_data->reg_offsets.control); break; case MV64XXX_I2C_ACTION_RCV_DATA: drv_data->msg->buf[drv_data->byte_posn++] = - readl(drv_data->reg_base + MV64XXX_I2C_REG_DATA); + readl(drv_data->reg_base + drv_data->reg_offsets.data); writel(drv_data->cntl_bits, - drv_data->reg_base + MV64XXX_I2C_REG_CONTROL); + drv_data->reg_base + drv_data->reg_offsets.control); break; case MV64XXX_I2C_ACTION_RCV_DATA_STOP: drv_data->msg->buf[drv_data->byte_posn++] = - readl(drv_data->reg_base + MV64XXX_I2C_REG_DATA); + readl(drv_data->reg_base + drv_data->reg_offsets.data); drv_data->cntl_bits &= ~MV64XXX_I2C_REG_CONTROL_INTEN; writel(drv_data->cntl_bits | MV64XXX_I2C_REG_CONTROL_STOP, - drv_data->reg_base + MV64XXX_I2C_REG_CONTROL); + drv_data->reg_base + drv_data->reg_offsets.control); drv_data->block = 0; wake_up(&drv_data->waitq); break; @@ -313,7 +379,7 @@ mv64xxx_i2c_do_action(struct mv64xxx_i2c_data *drv_data) case MV64XXX_I2C_ACTION_SEND_STOP: drv_data->cntl_bits &= ~MV64XXX_I2C_REG_CONTROL_INTEN; writel(drv_data->cntl_bits | MV64XXX_I2C_REG_CONTROL_STOP, - drv_data->reg_base + MV64XXX_I2C_REG_CONTROL); + drv_data->reg_base + drv_data->reg_offsets.control); drv_data->block = 0; wake_up(&drv_data->waitq); break; @@ -329,9 +395,9 @@ mv64xxx_i2c_intr(int irq, void *dev_id) irqreturn_t rc = IRQ_NONE; spin_lock_irqsave(&drv_data->lock, flags); - while (readl(drv_data->reg_base + MV64XXX_I2C_REG_CONTROL) & + while (readl(drv_data->reg_base + drv_data->reg_offsets.control) & MV64XXX_I2C_REG_CONTROL_IFLG) { - status = readl(drv_data->reg_base + MV64XXX_I2C_REG_STATUS); + status = readl(drv_data->reg_base + drv_data->reg_offsets.status); mv64xxx_i2c_fsm(drv_data, status); mv64xxx_i2c_do_action(drv_data); rc = IRQ_HANDLED; @@ -349,32 +415,6 @@ mv64xxx_i2c_intr(int irq, void *dev_id) ***************************************************************************** */ static void -mv64xxx_i2c_prepare_for_io(struct mv64xxx_i2c_data *drv_data, - struct i2c_msg *msg) -{ - u32 dir = 0; - - drv_data->msg = msg; - drv_data->byte_posn = 0; - drv_data->bytes_left = msg->len; - drv_data->aborting = 0; - drv_data->rc = 0; - drv_data->cntl_bits = MV64XXX_I2C_REG_CONTROL_ACK | - MV64XXX_I2C_REG_CONTROL_INTEN | MV64XXX_I2C_REG_CONTROL_TWSIEN; - - if (msg->flags & I2C_M_RD) - dir = 1; - - if (msg->flags & I2C_M_TEN) { - drv_data->addr1 = 0xf0 | (((u32)msg->addr & 0x300) >> 7) | dir; - drv_data->addr2 = (u32)msg->addr & 0xff; - } else { - drv_data->addr1 = ((u32)msg->addr & 0x7f) << 1 | dir; - drv_data->addr2 = 0; - } -} - -static void mv64xxx_i2c_wait_for_completion(struct mv64xxx_i2c_data *drv_data) { long time_left; @@ -414,36 +454,15 @@ mv64xxx_i2c_wait_for_completion(struct mv64xxx_i2c_data *drv_data) static int mv64xxx_i2c_execute_msg(struct mv64xxx_i2c_data *drv_data, struct i2c_msg *msg, - int is_first, int is_last) + int is_last) { unsigned long flags; spin_lock_irqsave(&drv_data->lock, flags); mv64xxx_i2c_prepare_for_io(drv_data, msg); - if (unlikely(msg->flags & I2C_M_NOSTART)) { /* Skip start/addr phases */ - if (drv_data->msg->flags & I2C_M_RD) { - /* No action to do, wait for slave to send a byte */ - drv_data->action = MV64XXX_I2C_ACTION_CONTINUE; - drv_data->state = - MV64XXX_I2C_STATE_WAITING_FOR_SLAVE_DATA; - } else { - drv_data->action = MV64XXX_I2C_ACTION_SEND_DATA; - drv_data->state = - MV64XXX_I2C_STATE_WAITING_FOR_SLAVE_ACK; - drv_data->bytes_left--; - } - } else { - if (is_first) { - drv_data->action = MV64XXX_I2C_ACTION_SEND_START; - drv_data->state = - MV64XXX_I2C_STATE_WAITING_FOR_START_COND; - } else { - drv_data->action = MV64XXX_I2C_ACTION_SEND_ADDR_1; - drv_data->state = - MV64XXX_I2C_STATE_WAITING_FOR_ADDR_1_ACK; - } - } + drv_data->action = MV64XXX_I2C_ACTION_SEND_START; + drv_data->state = MV64XXX_I2C_STATE_WAITING_FOR_START_COND; drv_data->send_stop = is_last; drv_data->block = 1; @@ -471,16 +490,20 @@ static int mv64xxx_i2c_xfer(struct i2c_adapter *adap, struct i2c_msg msgs[], int num) { struct mv64xxx_i2c_data *drv_data = i2c_get_adapdata(adap); - int i, rc; + int rc, ret = num; - for (i = 0; i < num; i++) { - rc = mv64xxx_i2c_execute_msg(drv_data, &msgs[i], - i == 0, i + 1 == num); - if (rc < 0) - return rc; - } + BUG_ON(drv_data->msgs != NULL); + drv_data->msgs = msgs; + drv_data->num_msgs = num; + + rc = mv64xxx_i2c_execute_msg(drv_data, &msgs[0], num == 1); + if (rc < 0) + ret = rc; + + drv_data->num_msgs = 0; + drv_data->msgs = NULL; - return num; + return ret; } static const struct i2c_algorithm mv64xxx_i2c_algo = { @@ -495,39 +518,12 @@ static const struct i2c_algorithm mv64xxx_i2c_algo = { * ***************************************************************************** */ -static int -mv64xxx_i2c_map_regs(struct platform_device *pd, - struct mv64xxx_i2c_data *drv_data) -{ - int size; - struct resource *r = platform_get_resource(pd, IORESOURCE_MEM, 0); - - if (!r) - return -ENODEV; - - size = resource_size(r); - - if (!request_mem_region(r->start, size, drv_data->adapter.name)) - return -EBUSY; - - drv_data->reg_base = ioremap(r->start, size); - drv_data->reg_base_p = r->start; - drv_data->reg_size = size; - - return 0; -} - -static void -mv64xxx_i2c_unmap_regs(struct mv64xxx_i2c_data *drv_data) -{ - if (drv_data->reg_base) { - iounmap(drv_data->reg_base); - release_mem_region(drv_data->reg_base_p, drv_data->reg_size); - } - - drv_data->reg_base = NULL; - drv_data->reg_base_p = 0; -} +static const struct of_device_id mv64xxx_i2c_of_match_table[] = { + { .compatible = "allwinner,sun4i-i2c", .data = &mv64xxx_i2c_regs_sun4i}, + { .compatible = "marvell,mv64xxx-i2c", .data = &mv64xxx_i2c_regs_mv64xxx}, + {} +}; +MODULE_DEVICE_TABLE(of, mv64xxx_i2c_of_match_table); #ifdef CONFIG_OF static int @@ -562,8 +558,10 @@ mv64xxx_find_baud_factors(const u32 req_freq, const u32 tclk, u32 *best_n, static int mv64xxx_of_config(struct mv64xxx_i2c_data *drv_data, - struct device_node *np) + struct device *dev) { + const struct of_device_id *device; + struct device_node *np = dev->of_node; u32 bus_freq, tclk; int rc = 0; @@ -580,7 +578,11 @@ mv64xxx_of_config(struct mv64xxx_i2c_data *drv_data, goto out; } tclk = clk_get_rate(drv_data->clk); - of_property_read_u32(np, "clock-frequency", &bus_freq); + + rc = of_property_read_u32(np, "clock-frequency", &bus_freq); + if (rc) + bus_freq = 100000; /* 100kHz by default */ + if (!mv64xxx_find_baud_factors(bus_freq, tclk, &drv_data->freq_n, &drv_data->freq_m)) { rc = -EINVAL; @@ -592,6 +594,13 @@ mv64xxx_of_config(struct mv64xxx_i2c_data *drv_data, * So hard code the value to 1 second. */ drv_data->adapter.timeout = HZ; + + device = of_match_device(mv64xxx_i2c_of_match_table, dev); + if (!device) + return -ENODEV; + + memcpy(&drv_data->reg_offsets, device->data, sizeof(drv_data->reg_offsets)); + out: return rc; #endif @@ -599,7 +608,7 @@ out: #else /* CONFIG_OF */ static int mv64xxx_of_config(struct mv64xxx_i2c_data *drv_data, - struct device_node *np) + struct device *dev) { return -ENODEV; } @@ -610,19 +619,21 @@ mv64xxx_i2c_probe(struct platform_device *pd) { struct mv64xxx_i2c_data *drv_data; struct mv64xxx_i2c_pdata *pdata = pd->dev.platform_data; + struct resource *r; int rc; if ((!pdata && !pd->dev.of_node)) return -ENODEV; - drv_data = kzalloc(sizeof(struct mv64xxx_i2c_data), GFP_KERNEL); + drv_data = devm_kzalloc(&pd->dev, sizeof(struct mv64xxx_i2c_data), + GFP_KERNEL); if (!drv_data) return -ENOMEM; - if (mv64xxx_i2c_map_regs(pd, drv_data)) { - rc = -ENODEV; - goto exit_kfree; - } + r = platform_get_resource(pd, IORESOURCE_MEM, 0); + drv_data->reg_base = devm_ioremap_resource(&pd->dev, r); + if (IS_ERR(drv_data->reg_base)) + return PTR_ERR(drv_data->reg_base); strlcpy(drv_data->adapter.name, MV64XXX_I2C_CTLR_NAME " adapter", sizeof(drv_data->adapter.name)); @@ -632,7 +643,7 @@ mv64xxx_i2c_probe(struct platform_device *pd) #if defined(CONFIG_HAVE_CLK) /* Not all platforms have a clk */ - drv_data->clk = clk_get(&pd->dev, NULL); + drv_data->clk = devm_clk_get(&pd->dev, NULL); if (!IS_ERR(drv_data->clk)) { clk_prepare(drv_data->clk); clk_enable(drv_data->clk); @@ -643,14 +654,15 @@ mv64xxx_i2c_probe(struct platform_device *pd) drv_data->freq_n = pdata->freq_n; drv_data->irq = platform_get_irq(pd, 0); drv_data->adapter.timeout = msecs_to_jiffies(pdata->timeout); + memcpy(&drv_data->reg_offsets, &mv64xxx_i2c_regs_mv64xxx, sizeof(drv_data->reg_offsets)); } else if (pd->dev.of_node) { - rc = mv64xxx_of_config(drv_data, pd->dev.of_node); + rc = mv64xxx_of_config(drv_data, &pd->dev); if (rc) - goto exit_unmap_regs; + goto exit_clk; } if (drv_data->irq < 0) { rc = -ENXIO; - goto exit_unmap_regs; + goto exit_clk; } drv_data->adapter.dev.parent = &pd->dev; @@ -664,13 +676,13 @@ mv64xxx_i2c_probe(struct platform_device *pd) mv64xxx_i2c_hw_init(drv_data); - if (request_irq(drv_data->irq, mv64xxx_i2c_intr, 0, - MV64XXX_I2C_CTLR_NAME, drv_data)) { + rc = request_irq(drv_data->irq, mv64xxx_i2c_intr, 0, + MV64XXX_I2C_CTLR_NAME, drv_data); + if (rc) { dev_err(&drv_data->adapter.dev, - "mv64xxx: Can't register intr handler irq: %d\n", - drv_data->irq); - rc = -EINVAL; - goto exit_unmap_regs; + "mv64xxx: Can't register intr handler irq%d: %d\n", + drv_data->irq, rc); + goto exit_clk; } else if ((rc = i2c_add_numbered_adapter(&drv_data->adapter)) != 0) { dev_err(&drv_data->adapter.dev, "mv64xxx: Can't add i2c adapter, rc: %d\n", -rc); @@ -681,9 +693,9 @@ mv64xxx_i2c_probe(struct platform_device *pd) return 0; - exit_free_irq: - free_irq(drv_data->irq, drv_data); - exit_unmap_regs: +exit_free_irq: + free_irq(drv_data->irq, drv_data); +exit_clk: #if defined(CONFIG_HAVE_CLK) /* Not all platforms have a clk */ if (!IS_ERR(drv_data->clk)) { @@ -691,9 +703,6 @@ mv64xxx_i2c_probe(struct platform_device *pd) clk_unprepare(drv_data->clk); } #endif - mv64xxx_i2c_unmap_regs(drv_data); - exit_kfree: - kfree(drv_data); return rc; } @@ -704,7 +713,6 @@ mv64xxx_i2c_remove(struct platform_device *dev) i2c_del_adapter(&drv_data->adapter); free_irq(drv_data->irq, drv_data); - mv64xxx_i2c_unmap_regs(drv_data); #if defined(CONFIG_HAVE_CLK) /* Not all platforms have a clk */ if (!IS_ERR(drv_data->clk)) { @@ -712,17 +720,10 @@ mv64xxx_i2c_remove(struct platform_device *dev) clk_unprepare(drv_data->clk); } #endif - kfree(drv_data); return 0; } -static const struct of_device_id mv64xxx_i2c_of_match_table[] = { - { .compatible = "marvell,mv64xxx-i2c", }, - {} -}; -MODULE_DEVICE_TABLE(of, mv64xxx_i2c_of_match_table); - static struct platform_driver mv64xxx_i2c_driver = { .probe = mv64xxx_i2c_probe, .remove = mv64xxx_i2c_remove, |