diff options
Diffstat (limited to 'drivers/i2c/busses/i2c-mpc.c')
| -rw-r--r-- | drivers/i2c/busses/i2c-mpc.c | 194 |
1 files changed, 150 insertions, 44 deletions
diff --git a/drivers/i2c/busses/i2c-mpc.c b/drivers/i2c/busses/i2c-mpc.c index a8ebb84e23f..6a32aa095f8 100644 --- a/drivers/i2c/busses/i2c-mpc.c +++ b/drivers/i2c/busses/i2c-mpc.c @@ -16,11 +16,12 @@ #include <linux/kernel.h> #include <linux/module.h> #include <linux/sched.h> -#include <linux/init.h> +#include <linux/of_address.h> +#include <linux/of_irq.h> #include <linux/of_platform.h> -#include <linux/of_i2c.h> #include <linux/slab.h> +#include <linux/clk.h> #include <linux/io.h> #include <linux/fsl_devices.h> #include <linux/i2c.h> @@ -64,6 +65,10 @@ struct mpc_i2c { struct i2c_adapter adap; int irq; u32 real_clk; +#ifdef CONFIG_PM_SLEEP + u8 fdr, dfsrr; +#endif + struct clk *clk_per; }; struct mpc_i2c_divider { @@ -110,7 +115,7 @@ static void mpc_i2c_fixup(struct mpc_i2c *i2c) for (k = 9; k; k--) { writeccr(i2c, 0); writeccr(i2c, CCR_MSTA | CCR_MTX | CCR_MEN); - udelay(delay_val); + readb(i2c->base + MPC_I2C_DR); writeccr(i2c, CCR_MEN); udelay(delay_val << 1); } @@ -172,7 +177,7 @@ static int i2c_wait(struct mpc_i2c *i2c, unsigned timeout, int writing) } #if defined(CONFIG_PPC_MPC52xx) || defined(CONFIG_PPC_MPC512x) -static const struct mpc_i2c_divider mpc_i2c_dividers_52xx[] __devinitconst = { +static const struct mpc_i2c_divider mpc_i2c_dividers_52xx[] = { {20, 0x20}, {22, 0x21}, {24, 0x22}, {26, 0x23}, {28, 0x24}, {30, 0x01}, {32, 0x25}, {34, 0x02}, {36, 0x26}, {40, 0x27}, {44, 0x04}, {48, 0x28}, @@ -193,7 +198,7 @@ static const struct mpc_i2c_divider mpc_i2c_dividers_52xx[] __devinitconst = { {10240, 0x9d}, {12288, 0x9e}, {15360, 0x9f} }; -static int __devinit mpc_i2c_get_fdr_52xx(struct device_node *node, u32 clock, +static int mpc_i2c_get_fdr_52xx(struct device_node *node, u32 clock, int prescaler, u32 *real_clk) { const struct mpc_i2c_divider *div = NULL; @@ -227,7 +232,7 @@ static int __devinit mpc_i2c_get_fdr_52xx(struct device_node *node, u32 clock, return (int)div->fdr; } -static void __devinit mpc_i2c_setup_52xx(struct device_node *node, +static void mpc_i2c_setup_52xx(struct device_node *node, struct mpc_i2c *i2c, u32 clock, u32 prescaler) { @@ -249,7 +254,7 @@ static void __devinit mpc_i2c_setup_52xx(struct device_node *node, fdr); } #else /* !(CONFIG_PPC_MPC52xx || CONFIG_PPC_MPC512x) */ -static void __devinit mpc_i2c_setup_52xx(struct device_node *node, +static void mpc_i2c_setup_52xx(struct device_node *node, struct mpc_i2c *i2c, u32 clock, u32 prescaler) { @@ -257,7 +262,7 @@ static void __devinit mpc_i2c_setup_52xx(struct device_node *node, #endif /* CONFIG_PPC_MPC52xx || CONFIG_PPC_MPC512x */ #ifdef CONFIG_PPC_MPC512x -static void __devinit mpc_i2c_setup_512x(struct device_node *node, +static void mpc_i2c_setup_512x(struct device_node *node, struct mpc_i2c *i2c, u32 clock, u32 prescaler) { @@ -285,7 +290,7 @@ static void __devinit mpc_i2c_setup_512x(struct device_node *node, mpc_i2c_setup_52xx(node, i2c, clock, prescaler); } #else /* CONFIG_PPC_MPC512x */ -static void __devinit mpc_i2c_setup_512x(struct device_node *node, +static void mpc_i2c_setup_512x(struct device_node *node, struct mpc_i2c *i2c, u32 clock, u32 prescaler) { @@ -293,7 +298,7 @@ static void __devinit mpc_i2c_setup_512x(struct device_node *node, #endif /* CONFIG_PPC_MPC512x */ #ifdef CONFIG_FSL_SOC -static const struct mpc_i2c_divider mpc_i2c_dividers_8xxx[] __devinitconst = { +static const struct mpc_i2c_divider mpc_i2c_dividers_8xxx[] = { {160, 0x0120}, {192, 0x0121}, {224, 0x0122}, {256, 0x0123}, {288, 0x0100}, {320, 0x0101}, {352, 0x0601}, {384, 0x0102}, {416, 0x0602}, {448, 0x0126}, {480, 0x0103}, {512, 0x0127}, @@ -313,7 +318,7 @@ static const struct mpc_i2c_divider mpc_i2c_dividers_8xxx[] __devinitconst = { {49152, 0x011e}, {61440, 0x011f} }; -static u32 __devinit mpc_i2c_get_sec_cfg_8xxx(void) +static u32 mpc_i2c_get_sec_cfg_8xxx(void) { struct device_node *node = NULL; u32 __iomem *reg; @@ -342,7 +347,7 @@ static u32 __devinit mpc_i2c_get_sec_cfg_8xxx(void) return val; } -static int __devinit mpc_i2c_get_fdr_8xxx(struct device_node *node, u32 clock, +static int mpc_i2c_get_fdr_8xxx(struct device_node *node, u32 clock, u32 prescaler, u32 *real_clk) { const struct mpc_i2c_divider *div = NULL; @@ -380,7 +385,7 @@ static int __devinit mpc_i2c_get_fdr_8xxx(struct device_node *node, u32 clock, return div ? (int)div->fdr : -EINVAL; } -static void __devinit mpc_i2c_setup_8xxx(struct device_node *node, +static void mpc_i2c_setup_8xxx(struct device_node *node, struct mpc_i2c *i2c, u32 clock, u32 prescaler) { @@ -405,7 +410,7 @@ static void __devinit mpc_i2c_setup_8xxx(struct device_node *node, } #else /* !CONFIG_FSL_SOC */ -static void __devinit mpc_i2c_setup_8xxx(struct device_node *node, +static void mpc_i2c_setup_8xxx(struct device_node *node, struct mpc_i2c *i2c, u32 clock, u32 prescaler) { @@ -454,7 +459,7 @@ static int mpc_write(struct mpc_i2c *i2c, int target, } static int mpc_read(struct mpc_i2c *i2c, int target, - u8 *data, int length, int restart) + u8 *data, int length, int restart, bool recv_len) { unsigned timeout = i2c->adap.timeout; int i, result; @@ -470,7 +475,7 @@ static int mpc_read(struct mpc_i2c *i2c, int target, return result; if (length) { - if (length == 1) + if (length == 1 && !recv_len) writeccr(i2c, CCR_MIEN | CCR_MEN | CCR_MSTA | CCR_TXAK); else writeccr(i2c, CCR_MIEN | CCR_MEN | CCR_MSTA); @@ -479,17 +484,46 @@ static int mpc_read(struct mpc_i2c *i2c, int target, } for (i = 0; i < length; i++) { + u8 byte; + result = i2c_wait(i2c, timeout, 0); if (result < 0) return result; - /* Generate txack on next to last byte */ - if (i == length - 2) - writeccr(i2c, CCR_MIEN | CCR_MEN | CCR_MSTA | CCR_TXAK); - /* Do not generate stop on last byte */ - if (i == length - 1) - writeccr(i2c, CCR_MIEN | CCR_MEN | CCR_MSTA | CCR_MTX); - data[i] = readb(i2c->base + MPC_I2C_DR); + /* + * For block reads, we have to know the total length (1st byte) + * before we can determine if we are done. + */ + if (i || !recv_len) { + /* Generate txack on next to last byte */ + if (i == length - 2) + writeccr(i2c, CCR_MIEN | CCR_MEN | CCR_MSTA + | CCR_TXAK); + /* Do not generate stop on last byte */ + if (i == length - 1) + writeccr(i2c, CCR_MIEN | CCR_MEN | CCR_MSTA + | CCR_MTX); + } + + byte = readb(i2c->base + MPC_I2C_DR); + + /* + * Adjust length if first received byte is length. + * The length is 1 length byte plus actually data length + */ + if (i == 0 && recv_len) { + if (byte == 0 || byte > I2C_SMBUS_BLOCK_MAX) + return -EPROTO; + length += byte; + /* + * For block reads, generate txack here if data length + * is 1 byte (total length is 2 bytes). + */ + if (length == 2) + writeccr(i2c, CCR_MIEN | CCR_MEN | CCR_MSTA + | CCR_TXAK); + } + data[i] = byte; } return length; @@ -532,20 +566,42 @@ static int mpc_xfer(struct i2c_adapter *adap, struct i2c_msg *msgs, int num) "Doing %s %d bytes to 0x%02x - %d of %d messages\n", pmsg->flags & I2C_M_RD ? "read" : "write", pmsg->len, pmsg->addr, i + 1, num); - if (pmsg->flags & I2C_M_RD) - ret = - mpc_read(i2c, pmsg->addr, pmsg->buf, pmsg->len, i); - else + if (pmsg->flags & I2C_M_RD) { + bool recv_len = pmsg->flags & I2C_M_RECV_LEN; + + ret = mpc_read(i2c, pmsg->addr, pmsg->buf, pmsg->len, i, + recv_len); + if (recv_len && ret > 0) + pmsg->len = ret; + } else { ret = mpc_write(i2c, pmsg->addr, pmsg->buf, pmsg->len, i); + } + } + mpc_i2c_stop(i2c); /* Initiate STOP */ + orig_jiffies = jiffies; + /* Wait until STOP is seen, allow up to 1 s */ + while (readb(i2c->base + MPC_I2C_SR) & CSR_MBB) { + if (time_after(jiffies, orig_jiffies + HZ)) { + u8 status = readb(i2c->base + MPC_I2C_SR); + + dev_dbg(i2c->dev, "timeout\n"); + if ((status & (CSR_MCF | CSR_MBB | CSR_RXAK)) != 0) { + writeb(status & ~CSR_MAL, + i2c->base + MPC_I2C_SR); + mpc_i2c_fixup(i2c); + } + return -EIO; + } + cond_resched(); } - mpc_i2c_stop(i2c); return (ret < 0) ? ret : num; } static u32 mpc_functionality(struct i2c_adapter *adap) { - return I2C_FUNC_I2C | I2C_FUNC_SMBUS_EMUL; + return I2C_FUNC_I2C | I2C_FUNC_SMBUS_EMUL + | I2C_FUNC_SMBUS_READ_BLOCK_DATA | I2C_FUNC_SMBUS_BLOCK_PROC_CALL; } static const struct i2c_algorithm mpc_algo = { @@ -555,13 +611,12 @@ static const struct i2c_algorithm mpc_algo = { static struct i2c_adapter mpc_ops = { .owner = THIS_MODULE, - .name = "MPC adapter", .algo = &mpc_algo, .timeout = HZ, }; static const struct of_device_id mpc_i2c_of_match[]; -static int __devinit fsl_i2c_probe(struct platform_device *op) +static int fsl_i2c_probe(struct platform_device *op) { const struct of_device_id *match; struct mpc_i2c *i2c; @@ -569,6 +624,9 @@ static int __devinit fsl_i2c_probe(struct platform_device *op) u32 clock = MPC_I2C_CLOCK_LEGACY; int result = 0; int plen; + struct resource res; + struct clk *clk; + int err; match = of_match_device(mpc_i2c_of_match, &op->dev); if (!match) @@ -599,6 +657,21 @@ static int __devinit fsl_i2c_probe(struct platform_device *op) } } + /* + * enable clock for the I2C peripheral (non fatal), + * keep a reference upon successful allocation + */ + clk = devm_clk_get(&op->dev, NULL); + if (!IS_ERR(clk)) { + err = clk_prepare_enable(clk); + if (err) { + dev_err(&op->dev, "failed to enable clock\n"); + goto fail_request; + } else { + i2c->clk_per = clk; + } + } + if (of_get_property(op->dev.of_node, "fsl,preserve-clocking", NULL)) { clock = MPC_I2C_CLOCK_PRESERVE; } else { @@ -609,7 +682,7 @@ static int __devinit fsl_i2c_probe(struct platform_device *op) } if (match->data) { - struct mpc_i2c_data *data = match->data; + const struct mpc_i2c_data *data = match->data; data->setup(op->dev.of_node, i2c, clock, data->prescaler); } else { /* Backwards compatibility */ @@ -625,9 +698,12 @@ static int __devinit fsl_i2c_probe(struct platform_device *op) } dev_info(i2c->dev, "timeout %u us\n", mpc_ops.timeout * 1000000 / HZ); - dev_set_drvdata(&op->dev, i2c); + platform_set_drvdata(op, i2c); i2c->adap = mpc_ops; + of_address_to_resource(op->dev.of_node, 0, &res); + scnprintf(i2c->adap.name, sizeof(i2c->adap.name), + "MPC adapter at 0x%llx", (unsigned long long)res.start); i2c_set_adapdata(&i2c->adap, i2c); i2c->adap.dev.parent = &op->dev; i2c->adap.dev.of_node = of_node_get(op->dev.of_node); @@ -637,12 +713,12 @@ static int __devinit fsl_i2c_probe(struct platform_device *op) dev_err(i2c->dev, "failed to add adapter\n"); goto fail_add; } - of_i2c_register_devices(&i2c->adap); return result; fail_add: - dev_set_drvdata(&op->dev, NULL); + if (i2c->clk_per) + clk_disable_unprepare(i2c->clk_per); free_irq(i2c->irq, i2c); fail_request: irq_dispose_mapping(i2c->irq); @@ -652,12 +728,14 @@ static int __devinit fsl_i2c_probe(struct platform_device *op) return result; }; -static int __devexit fsl_i2c_remove(struct platform_device *op) +static int fsl_i2c_remove(struct platform_device *op) { - struct mpc_i2c *i2c = dev_get_drvdata(&op->dev); + struct mpc_i2c *i2c = platform_get_drvdata(op); i2c_del_adapter(&i2c->adap); - dev_set_drvdata(&op->dev, NULL); + + if (i2c->clk_per) + clk_disable_unprepare(i2c->clk_per); if (i2c->irq) free_irq(i2c->irq, i2c); @@ -668,24 +746,51 @@ static int __devexit fsl_i2c_remove(struct platform_device *op) return 0; }; -static struct mpc_i2c_data mpc_i2c_data_512x __devinitdata = { +#ifdef CONFIG_PM_SLEEP +static int mpc_i2c_suspend(struct device *dev) +{ + struct mpc_i2c *i2c = dev_get_drvdata(dev); + + i2c->fdr = readb(i2c->base + MPC_I2C_FDR); + i2c->dfsrr = readb(i2c->base + MPC_I2C_DFSRR); + + return 0; +} + +static int mpc_i2c_resume(struct device *dev) +{ + struct mpc_i2c *i2c = dev_get_drvdata(dev); + + writeb(i2c->fdr, i2c->base + MPC_I2C_FDR); + writeb(i2c->dfsrr, i2c->base + MPC_I2C_DFSRR); + + return 0; +} + +static SIMPLE_DEV_PM_OPS(mpc_i2c_pm_ops, mpc_i2c_suspend, mpc_i2c_resume); +#define MPC_I2C_PM_OPS (&mpc_i2c_pm_ops) +#else +#define MPC_I2C_PM_OPS NULL +#endif + +static const struct mpc_i2c_data mpc_i2c_data_512x = { .setup = mpc_i2c_setup_512x, }; -static struct mpc_i2c_data mpc_i2c_data_52xx __devinitdata = { +static const struct mpc_i2c_data mpc_i2c_data_52xx = { .setup = mpc_i2c_setup_52xx, }; -static struct mpc_i2c_data mpc_i2c_data_8313 __devinitdata = { +static const struct mpc_i2c_data mpc_i2c_data_8313 = { .setup = mpc_i2c_setup_8xxx, }; -static struct mpc_i2c_data mpc_i2c_data_8543 __devinitdata = { +static const struct mpc_i2c_data mpc_i2c_data_8543 = { .setup = mpc_i2c_setup_8xxx, .prescaler = 2, }; -static struct mpc_i2c_data mpc_i2c_data_8544 __devinitdata = { +static const struct mpc_i2c_data mpc_i2c_data_8544 = { .setup = mpc_i2c_setup_8xxx, .prescaler = 3, }; @@ -707,11 +812,12 @@ MODULE_DEVICE_TABLE(of, mpc_i2c_of_match); /* Structure for a device driver */ static struct platform_driver mpc_i2c_driver = { .probe = fsl_i2c_probe, - .remove = __devexit_p(fsl_i2c_remove), + .remove = fsl_i2c_remove, .driver = { .owner = THIS_MODULE, .name = DRV_NAME, .of_match_table = mpc_i2c_of_match, + .pm = MPC_I2C_PM_OPS, }, }; |
