diff options
Diffstat (limited to 'drivers/i2c/busses/i2c-sh_mobile.c')
-rw-r--r-- | drivers/i2c/busses/i2c-sh_mobile.c | 225 |
1 files changed, 107 insertions, 118 deletions
diff --git a/drivers/i2c/busses/i2c-sh_mobile.c b/drivers/i2c/busses/i2c-sh_mobile.c index 1d79585ba4b3..8b5e79cb4468 100644 --- a/drivers/i2c/busses/i2c-sh_mobile.c +++ b/drivers/i2c/busses/i2c-sh_mobile.c @@ -32,6 +32,7 @@ #include <linux/clk.h> #include <linux/io.h> #include <linux/slab.h> +#include <linux/of_device.h> #include <linux/i2c/i2c-sh_mobile.h> /* Transmit operation: */ @@ -139,6 +140,10 @@ struct sh_mobile_i2c_data { bool send_stop; }; +struct sh_mobile_dt_config { + int clks_per_count; +}; + #define IIC_FLAG_HAS_ICIC67 (1 << 0) #define STANDARD_MODE 100000 @@ -194,7 +199,7 @@ static void iic_set_clr(struct sh_mobile_i2c_data *pd, int offs, iic_wr(pd, offs, (iic_rd(pd, offs) | set) & ~clr); } -static u32 sh_mobile_i2c_iccl(unsigned long count_khz, u32 tLOW, u32 tf, int offset) +static u32 sh_mobile_i2c_iccl(unsigned long count_khz, u32 tLOW, u32 tf) { /* * Conditional expression: @@ -206,10 +211,10 @@ static u32 sh_mobile_i2c_iccl(unsigned long count_khz, u32 tLOW, u32 tf, int off * account the fall time of SCL signal (tf). Default tf value * should be 0.3 us, for safety. */ - return (((count_khz * (tLOW + tf)) + 5000) / 10000) + offset; + return (((count_khz * (tLOW + tf)) + 5000) / 10000); } -static u32 sh_mobile_i2c_icch(unsigned long count_khz, u32 tHIGH, u32 tf, int offset) +static u32 sh_mobile_i2c_icch(unsigned long count_khz, u32 tHIGH, u32 tf) { /* * Conditional expression: @@ -225,52 +230,58 @@ static u32 sh_mobile_i2c_icch(unsigned long count_khz, u32 tHIGH, u32 tf, int of * to take into account the fall time of SDA signal (tf) at START * condition, in order to meet both tHIGH and tHD;STA specs. */ - return (((count_khz * (tHIGH + tf)) + 5000) / 10000) + offset; + return (((count_khz * (tHIGH + tf)) + 5000) / 10000); } -static void sh_mobile_i2c_init(struct sh_mobile_i2c_data *pd) +static int sh_mobile_i2c_init(struct sh_mobile_i2c_data *pd) { unsigned long i2c_clk_khz; u32 tHIGH, tLOW, tf; - int offset; + uint16_t max_val; /* Get clock rate after clock is enabled */ clk_prepare_enable(pd->clk); i2c_clk_khz = clk_get_rate(pd->clk) / 1000; + clk_disable_unprepare(pd->clk); i2c_clk_khz /= pd->clks_per_count; if (pd->bus_speed == STANDARD_MODE) { tLOW = 47; /* tLOW = 4.7 us */ tHIGH = 40; /* tHD;STA = tHIGH = 4.0 us */ tf = 3; /* tf = 0.3 us */ - offset = 0; /* No offset */ } else if (pd->bus_speed == FAST_MODE) { tLOW = 13; /* tLOW = 1.3 us */ tHIGH = 6; /* tHD;STA = tHIGH = 0.6 us */ tf = 3; /* tf = 0.3 us */ - offset = 0; /* No offset */ } else { dev_err(pd->dev, "unrecognized bus speed %lu Hz\n", pd->bus_speed); - goto out; + return -EINVAL; + } + + pd->iccl = sh_mobile_i2c_iccl(i2c_clk_khz, tLOW, tf); + pd->icch = sh_mobile_i2c_icch(i2c_clk_khz, tHIGH, tf); + + max_val = pd->flags & IIC_FLAG_HAS_ICIC67 ? 0x1ff : 0xff; + if (pd->iccl > max_val || pd->icch > max_val) { + dev_err(pd->dev, "timing values out of range: L/H=0x%x/0x%x\n", + pd->iccl, pd->icch); + return -EINVAL; } - pd->iccl = sh_mobile_i2c_iccl(i2c_clk_khz, tLOW, tf, offset); /* one more bit of ICCL in ICIC */ - if ((pd->iccl > 0xff) && (pd->flags & IIC_FLAG_HAS_ICIC67)) + if (pd->iccl & 0x100) pd->icic |= ICIC_ICCLB8; else pd->icic &= ~ICIC_ICCLB8; - pd->icch = sh_mobile_i2c_icch(i2c_clk_khz, tHIGH, tf, offset); /* one more bit of ICCH in ICIC */ - if ((pd->icch > 0xff) && (pd->flags & IIC_FLAG_HAS_ICIC67)) + if (pd->icch & 0x100) pd->icic |= ICIC_ICCHB8; else pd->icic &= ~ICIC_ICCHB8; -out: - clk_disable_unprepare(pd->clk); + return 0; } static void activate_ch(struct sh_mobile_i2c_data *pd) @@ -316,7 +327,7 @@ static unsigned char i2c_op(struct sh_mobile_i2c_data *pd, switch (op) { case OP_START: /* issue start and trigger DTE interrupt */ - iic_wr(pd, ICCR, 0x94); + iic_wr(pd, ICCR, ICCR_ICE | ICCR_TRS | ICCR_BBSY); break; case OP_TX_FIRST: /* disable DTE interrupt and write data */ iic_wr(pd, ICIC, ICIC_WAITE | ICIC_ALE | ICIC_TACKE); @@ -327,10 +338,11 @@ static unsigned char i2c_op(struct sh_mobile_i2c_data *pd, break; case OP_TX_STOP: /* write data and issue a stop afterwards */ iic_wr(pd, ICDR, data); - iic_wr(pd, ICCR, pd->send_stop ? 0x90 : 0x94); + iic_wr(pd, ICCR, pd->send_stop ? ICCR_ICE | ICCR_TRS + : ICCR_ICE | ICCR_TRS | ICCR_BBSY); break; case OP_TX_TO_RX: /* select read mode */ - iic_wr(pd, ICCR, 0x81); + iic_wr(pd, ICCR, ICCR_ICE | ICCR_SCP); break; case OP_RX: /* just read data */ ret = iic_rd(pd, ICDR); @@ -338,13 +350,13 @@ static unsigned char i2c_op(struct sh_mobile_i2c_data *pd, case OP_RX_STOP: /* enable DTE interrupt, issue stop */ iic_wr(pd, ICIC, ICIC_DTEE | ICIC_WAITE | ICIC_ALE | ICIC_TACKE); - iic_wr(pd, ICCR, 0xc0); + iic_wr(pd, ICCR, ICCR_ICE | ICCR_RACK); break; case OP_RX_STOP_DATA: /* enable DTE interrupt, read data, issue stop */ iic_wr(pd, ICIC, ICIC_DTEE | ICIC_WAITE | ICIC_ALE | ICIC_TACKE); ret = iic_rd(pd, ICDR); - iic_wr(pd, ICCR, 0xc0); + iic_wr(pd, ICCR, ICCR_ICE | ICCR_RACK); break; } @@ -479,7 +491,7 @@ static int start_ch(struct sh_mobile_i2c_data *pd, struct i2c_msg *usr_msg, { if (usr_msg->len == 0 && (usr_msg->flags & I2C_M_RD)) { dev_err(pd->dev, "Unsupported zero length i2c read\n"); - return -EIO; + return -EOPNOTSUPP; } if (do_init) { @@ -514,17 +526,12 @@ static int poll_dte(struct sh_mobile_i2c_data *pd) break; if (val & ICSR_TACK) - return -EIO; + return -ENXIO; udelay(10); } - if (!i) { - dev_warn(pd->dev, "Timeout polling for DTE!\n"); - return -ETIMEDOUT; - } - - return 0; + return i ? 0 : -ETIMEDOUT; } static int poll_busy(struct sh_mobile_i2c_data *pd) @@ -542,20 +549,18 @@ static int poll_busy(struct sh_mobile_i2c_data *pd) */ if (!(val & ICSR_BUSY)) { /* handle missing acknowledge and arbitration lost */ - if ((val | pd->sr) & (ICSR_TACK | ICSR_AL)) - return -EIO; + val |= pd->sr; + if (val & ICSR_TACK) + return -ENXIO; + if (val & ICSR_AL) + return -EAGAIN; break; } udelay(10); } - if (!i) { - dev_err(pd->dev, "Polling timed out\n"); - return -ETIMEDOUT; - } - - return 0; + return i ? 0 : -ETIMEDOUT; } static int sh_mobile_i2c_xfer(struct i2c_adapter *adapter, @@ -617,42 +622,44 @@ static struct i2c_algorithm sh_mobile_i2c_algorithm = { .master_xfer = sh_mobile_i2c_xfer, }; -static int sh_mobile_i2c_hook_irqs(struct platform_device *dev, int hook) +static const struct sh_mobile_dt_config default_dt_config = { + .clks_per_count = 1, +}; + +static const struct sh_mobile_dt_config rcar_gen2_dt_config = { + .clks_per_count = 2, +}; + +static const struct of_device_id sh_mobile_i2c_dt_ids[] = { + { .compatible = "renesas,rmobile-iic", .data = &default_dt_config }, + { .compatible = "renesas,iic-r8a7790", .data = &rcar_gen2_dt_config }, + { .compatible = "renesas,iic-r8a7791", .data = &rcar_gen2_dt_config }, + { .compatible = "renesas,iic-r8a7792", .data = &rcar_gen2_dt_config }, + { .compatible = "renesas,iic-r8a7793", .data = &rcar_gen2_dt_config }, + { .compatible = "renesas,iic-r8a7794", .data = &rcar_gen2_dt_config }, + {}, +}; +MODULE_DEVICE_TABLE(of, sh_mobile_i2c_dt_ids); + +static int sh_mobile_i2c_hook_irqs(struct platform_device *dev) { struct resource *res; - int ret = -ENXIO; - int n, k = 0; + resource_size_t n; + int k = 0, ret; while ((res = platform_get_resource(dev, IORESOURCE_IRQ, k))) { - for (n = res->start; hook && n <= res->end; n++) { - if (request_irq(n, sh_mobile_i2c_isr, 0, - dev_name(&dev->dev), dev)) { - for (n--; n >= res->start; n--) - free_irq(n, dev); - - goto rollback; + for (n = res->start; n <= res->end; n++) { + ret = devm_request_irq(&dev->dev, n, sh_mobile_i2c_isr, + 0, dev_name(&dev->dev), dev); + if (ret) { + dev_err(&dev->dev, "cannot request IRQ %pa\n", &n); + return ret; } } k++; } - if (hook) - return k > 0 ? 0 : -ENOENT; - - ret = 0; - - rollback: - k--; - - while (k >= 0) { - res = platform_get_resource(dev, IORESOURCE_IRQ, k); - for (n = res->start; n <= res->end; n++) - free_irq(n, dev); - - k--; - } - - return ret; + return k > 0 ? 0 : -ENOENT; } static int sh_mobile_i2c_probe(struct platform_device *dev) @@ -661,62 +668,64 @@ static int sh_mobile_i2c_probe(struct platform_device *dev) struct sh_mobile_i2c_data *pd; struct i2c_adapter *adap; struct resource *res; - int size; int ret; + u32 bus_speed; - pd = kzalloc(sizeof(struct sh_mobile_i2c_data), GFP_KERNEL); - if (pd == NULL) { - dev_err(&dev->dev, "cannot allocate private data\n"); + pd = devm_kzalloc(&dev->dev, sizeof(struct sh_mobile_i2c_data), GFP_KERNEL); + if (!pd) return -ENOMEM; - } - pd->clk = clk_get(&dev->dev, NULL); + pd->clk = devm_clk_get(&dev->dev, NULL); if (IS_ERR(pd->clk)) { dev_err(&dev->dev, "cannot get clock\n"); - ret = PTR_ERR(pd->clk); - goto err; + return PTR_ERR(pd->clk); } - ret = sh_mobile_i2c_hook_irqs(dev, 1); - if (ret) { - dev_err(&dev->dev, "cannot request IRQ\n"); - goto err_clk; - } + ret = sh_mobile_i2c_hook_irqs(dev); + if (ret) + return ret; pd->dev = &dev->dev; platform_set_drvdata(dev, pd); res = platform_get_resource(dev, IORESOURCE_MEM, 0); - if (res == NULL) { - dev_err(&dev->dev, "cannot find IO resource\n"); - ret = -ENOENT; - goto err_irq; - } - - size = resource_size(res); - pd->reg = ioremap(res->start, size); - if (pd->reg == NULL) { - dev_err(&dev->dev, "cannot map IO\n"); - ret = -ENXIO; - goto err_irq; - } + pd->reg = devm_ioremap_resource(&dev->dev, res); + if (IS_ERR(pd->reg)) + return PTR_ERR(pd->reg); /* Use platform data bus speed or STANDARD_MODE */ - pd->bus_speed = STANDARD_MODE; - if (pdata && pdata->bus_speed) - pd->bus_speed = pdata->bus_speed; + ret = of_property_read_u32(dev->dev.of_node, "clock-frequency", &bus_speed); + pd->bus_speed = ret ? STANDARD_MODE : bus_speed; + pd->clks_per_count = 1; - if (pdata && pdata->clks_per_count) - pd->clks_per_count = pdata->clks_per_count; + + if (dev->dev.of_node) { + const struct of_device_id *match; + + match = of_match_device(sh_mobile_i2c_dt_ids, &dev->dev); + if (match) { + const struct sh_mobile_dt_config *config; + + config = match->data; + pd->clks_per_count = config->clks_per_count; + } + } else { + if (pdata && pdata->bus_speed) + pd->bus_speed = pdata->bus_speed; + if (pdata && pdata->clks_per_count) + pd->clks_per_count = pdata->clks_per_count; + } /* The IIC blocks on SH-Mobile ARM processors * come with two new bits in ICIC. */ - if (size > 0x17) + if (resource_size(res) > 0x17) pd->flags |= IIC_FLAG_HAS_ICIC67; - sh_mobile_i2c_init(pd); + ret = sh_mobile_i2c_init(pd); + if (ret) + return ret; /* Enable Runtime PM for this device. * @@ -750,24 +759,14 @@ static int sh_mobile_i2c_probe(struct platform_device *dev) ret = i2c_add_numbered_adapter(adap); if (ret < 0) { dev_err(&dev->dev, "cannot add numbered adapter\n"); - goto err_all; + return ret; } dev_info(&dev->dev, - "I2C adapter %d with bus speed %lu Hz (L/H=%x/%x)\n", + "I2C adapter %d with bus speed %lu Hz (L/H=0x%x/0x%x)\n", adap->nr, pd->bus_speed, pd->iccl, pd->icch); return 0; - - err_all: - iounmap(pd->reg); - err_irq: - sh_mobile_i2c_hook_irqs(dev, 0); - err_clk: - clk_put(pd->clk); - err: - kfree(pd); - return ret; } static int sh_mobile_i2c_remove(struct platform_device *dev) @@ -775,11 +774,7 @@ static int sh_mobile_i2c_remove(struct platform_device *dev) struct sh_mobile_i2c_data *pd = platform_get_drvdata(dev); i2c_del_adapter(&pd->adap); - iounmap(pd->reg); - sh_mobile_i2c_hook_irqs(dev, 0); - clk_put(pd->clk); pm_runtime_disable(&dev->dev); - kfree(pd); return 0; } @@ -800,12 +795,6 @@ static const struct dev_pm_ops sh_mobile_i2c_dev_pm_ops = { .runtime_resume = sh_mobile_i2c_runtime_nop, }; -static const struct of_device_id sh_mobile_i2c_dt_ids[] = { - { .compatible = "renesas,rmobile-iic", }, - {}, -}; -MODULE_DEVICE_TABLE(of, sh_mobile_i2c_dt_ids); - static struct platform_driver sh_mobile_i2c_driver = { .driver = { .name = "i2c-sh_mobile", |