/* * (C) Copyright 2003-2004 * Humboldt Solutions Ltd, adrian@humboldt.co.uk. * This is a combined i2c adapter and algorithm driver for the * MPC107/Tsi107 PowerPC northbridge and processors that include * the same I2C unit (8240, 8245, 85xx). * * Release 0.8 * * This file is licensed under the terms of the GNU General Public * License version 2. This program is licensed "as is" without any * warranty of any kind, whether express or implied. */ #include #include #include #include #include #include #include #include #include #include #include #include #include #define DRV_NAME "mpc-i2c" #define MPC_I2C_FDR 0x04 #define MPC_I2C_CR 0x08 #define MPC_I2C_SR 0x0c #define MPC_I2C_DR 0x10 #define MPC_I2C_DFSRR 0x14 #define CCR_MEN 0x80 #define CCR_MIEN 0x40 #define CCR_MSTA 0x20 #define CCR_MTX 0x10 #define CCR_TXAK 0x08 #define CCR_RSTA 0x04 #define CSR_MCF 0x80 #define CSR_MAAS 0x40 #define CSR_MBB 0x20 #define CSR_MAL 0x10 #define CSR_SRW 0x04 #define CSR_MIF 0x02 #define CSR_RXAK 0x01 struct mpc_i2c { struct device *dev; void __iomem *base; u32 interrupt; wait_queue_head_t queue; struct i2c_adapter adap; int irq; }; struct mpc_i2c_divider { u16 divider; u16 fdr; /* including dfsrr */ }; struct mpc_i2c_data { void (*setclock)(struct device_node *node, struct mpc_i2c *i2c, u32 clock, u32 prescaler); u32 prescaler; }; static inline void writeccr(struct mpc_i2c *i2c, u32 x) { writeb(x, i2c->base + MPC_I2C_CR); } static irqreturn_t mpc_i2c_isr(int irq, void *dev_id) { struct mpc_i2c *i2c = dev_id; if (readb(i2c->base + MPC_I2C_SR) & CSR_MIF) { /* Read again to allow register to stabilise */ i2c->interrupt = readb(i2c->base + MPC_I2C_SR); writeb(0, i2c->base + MPC_I2C_SR); wake_up(&i2c->queue); } return IRQ_HANDLED; } /* Sometimes 9th clock pulse isn't generated, and slave doesn't release * the bus, because it wants to send ACK. * Following sequence of enabling/disabling and sending start/stop generates * the pulse, so it's all OK. */ static void mpc_i2c_fixup(struct mpc_i2c *i2c) { writeccr(i2c, 0); udelay(30); writeccr(i2c, CCR_MEN); udelay(30); writeccr(i2c, CCR_MSTA | CCR_MTX); udelay(30); writeccr(i2c, CCR_MSTA | CCR_MTX | CCR_MEN); udelay(30); writeccr(i2c, CCR_MEN); udelay(30); } static int i2c_wait(struct mpc_i2c *i2c, unsigned timeout, int writing) { unsigned long orig_jiffies = jiffies; u32 x; int result = 0; if (i2c->irq == NO_IRQ) { while (!(readb(i2c->base + MPC_I2C_SR) & CSR_MIF)) { schedule(); if (time_after(jiffies, orig_jiffies + timeout)) { dev_dbg(i2c->dev, "timeout\n"); writeccr(i2c, 0); result = -EIO; break; } } x = readb(i2c->base + MPC_I2C_SR); writeb(0, i2c->base + MPC_I2C_SR); } else { /* Interrupt mode */ result = wait_event_timeout(i2c->queue, (i2c->interrupt & CSR_MIF), timeout); if (unlikely(!(i2c->interrupt & CSR_MIF))) { dev_dbg(i2c->dev, "wait timeout\n"); writeccr(i2c, 0); result = -ETIMEDOUT; } x = i2c->interrupt; i2c->interrupt = 0; } if (result < 0) return result; if (!(x & CSR_MCF)) { dev_dbg(i2c->dev, "unfinished\n"); return -EIO; } if (x & CSR_MAL) { dev_dbg(i2c->dev, "MAL\n"); return -EIO; } if (writing && (x & CSR_RXAK)) { dev_dbg(i2c->dev, "No RXAK\n"); /* generate stop */ writeccr(i2c, CCR_MEN); return -EIO; } return 0; } #ifdef CONFIG_PPC_MPC52xx static const struct mpc_i2c_divider mpc_i2c_dividers_52xx[] __devinitconst = { {20, 0x20}, {22, 0x21}, {24, 0x22}, {26, 0x23}, {28, 0x24}, {30, 0x01}, {32, 0x25}, {34, 0x02}, {36, 0x26}, {40, 0x27}, {44, 0x04}, {48, 0x28}, {52, 0x63}, {56, 0x29}, {60, 0x41}, {64, 0x2a}, {68, 0x07}, {72, 0x2b}, {80, 0x2c}, {88, 0x09}, {96, 0x2d}, {104, 0x0a}, {112, 0x2e}, {120, 0x81}, {128, 0x2f}, {136, 0x47}, {144, 0x0c}, {160, 0x30}, {176, 0x49}, {192, 0x31}, {208, 0x4a}, {224, 0x32}, {240, 0x0f}, {256, 0x33}, {272, 0x87}, {288, 0x10}, {320, 0x34}, {352, 0x89}, {384, 0x35}, {416, 0x8a}, {448, 0x36}, {480, 0x13}, {512, 0x37}, {576, 0x14}, {640, 0x38}, {768, 0x39}, {896, 0x3a}, {960, 0x17}, {1024, 0x3b}, {1152, 0x18}, {1280, 0x3c}, {1536, 0x3d}, {1792, 0x3e}, {1920, 0x1b}, {2048, 0x3f}, {2304, 0x1c}, {2560, 0x1d}, {3072, 0x1e}, {3584, 0x7e}, {3840, 0x1f}, {4096, 0x7f}, {4608, 0x5c}, {5120, 0x5d}, {6144, 0x5e}, {7168, 0xbe}, {7680, 0x5f}, {8192, 0xbf}, {9216, 0x9c}, {10240, 0x9d}, {12288, 0x9e}, {15360, 0x9f} }; static int __devinit mpc_i2c_get_fdr_52xx(struct device_node *node, u32 clock, int prescaler) { const struct mpc_i2c_divider *div = NULL; unsigned int pvr = mfspr(SPRN_PVR); u32 divider; int i; if (!clock) return -EINVAL; /* Determine divider value */ divider = mpc5xxx_get_bus_frequency(node) / clock; /* * We want to choose an FDR/DFSR that generates an I2C bus speed that * is equal to or lower than the requested speed. */ for (i = 0; i < ARRAY_SIZE(mpc_i2c_dividers_52xx); i++) { div = &mpc_i2c_dividers_52xx[i]; /* Old MPC5200 rev A CPUs do not support the high bits */ if (div->fdr & 0xc0 && pvr == 0x80822011) continue; if (div->divider >= divider) break; } return div ? (int)div->fdr : -EINVAL; } static void __devinit mpc_i2c_setclock_52xx(struct device_node *node, struct mpc_i2c *i2c, u32 clock, u32 prescaler) { int ret, fdr; ret = mpc_i2c_get_fdr_52xx(node, clock, prescaler); fdr = (ret >= 0) ? ret : 0x3f; /* backward compatibility */ writeb(fdr & 0xff, i2c->base + MPC_I2C_FDR); if (ret >= 0) dev_info(i2c->dev, "clock %d Hz (fdr=%d)\n", clock, fdr); } #else /* !CONFIG_PPC_MPC52xx */ static void __devinit mpc_i2c_setclock_52xx(struct device_node *node, struct mpc_i2c *i2c, u32 clock, u32 prescaler) { } #endif /* CONFIG_PPC_MPC52xx*/ #ifdef CONFIG_FSL_SOC static const struct mpc_i2c_divider mpc_i2c_dividers_8xxx[] __devinitconst = { {160, 0x0120}, {192, 0x0121}, {224, 0x0122}, {256, 0x0123}, {288, 0x0100}, {320, 0x0101}, {352, 0x0601}, {384, 0x0102}, {416, 0x0602}, {448, 0x0126}, {480, 0x0103}, {512, 0x0127}, {544, 0x0b03}, {576, 0x0104}, {608, 0x1603}, {640, 0x0105}, {672, 0x2003}, {704, 0x0b05}, {736, 0x2b03}, {768, 0x0106}, {800, 0x3603}, {832, 0x0b06}, {896, 0x012a}, {960, 0x0107}, {1024, 0x012b}, {1088, 0x1607}, {1152, 0x0108}, {1216, 0x2b07}, {1280, 0x0109}, {1408, 0x1609}, {1536, 0x010a}, {1664, 0x160a}, {1792, 0x012e}, {1920, 0x010b}, {2048, 0x012f}, {2176, 0x2b0b}, {2304, 0x010c}, {2560, 0x010d}, {2816, 0x2b0d}, {3072, 0x010e}, {3328, 0x2b0e}, {3584, 0x0132}, {3840, 0x010f}, {4096, 0x0133}, {4608, 0x0110}, {5120, 0x0111}, {6144, 0x0112}, {7168, 0x0136}, {7680, 0x0113}, {8192, 0x0137}, {9216, 0x0114}, {10240, 0x0115}, {12288, 0x0116}, {14336, 0x013a}, {15360, 0x0117}, {16384, 0x013b}, {18432, 0x0118}, {20480, 0x0119}, {24576, 0x011a}, {28672, 0x013e}, {30720, 0x011b}, {32768, 0x013f}, {36864, 0x011c}, {40960, 0x011d}, {49152, 0x011e}, {61440, 0x011f} }; static u32 __devinit mpc_i2c_get_sec_cfg_8xxx(void) { struct device_node *node = NULL; u32 __iomem *reg; u32 val = 0; node = of_find_node_by_name(NULL, "global-utilities"); if (node) { const u32 *prop = of_get_property(node, "reg", NULL); if (prop) { /* * Map and check POR Device Status Register 2 * (PORDEVSR2) at 0xE0014 */ reg = ioremap(get_immrbase() + *prop + 0x14, 0x4); if (!reg) printk(KERN_ERR "Error: couldn't map PORDEVSR2\n"); else val = in_be32(reg) & 0x00000080; /* sec-cfg */ iounmap(reg); } } if (node) of_node_put(node); return val; } static int __devinit mpc_i2c_get_fdr_8xxx(struct device_node *node, u32 clock, u32 prescaler) { const struct mpc_i2c_divider *div = NULL; u32 divider; int i; if (!clock) return -EINVAL; /* Determine proper divider value */ if (of_device_is_compatible(node, "fsl,mpc8544-i2c")) prescaler = mpc_i2c_get_sec_cfg_8xxx() ? 3 : 2; if (!prescaler) prescaler = 1; divider = fsl_get_sys_freq() / clock / prescaler; pr_debug("I2C: src_clock=%d clock=%d divider=%d\n", fsl_get_sys_freq(), clock, divider); /* * We want to choose an FDR/DFSR that generates an I2C bus speed that * is equal to or lower than the requested speed. */ for (i = 0; i < ARRAY_SIZE(mpc_i2c_dividers_8xxx); i++) { div = &mpc_i2c_dividers_8xxx[i]; if (div->divider >= divider) break; } return div ? (int)div->fdr : -EINVAL; } static void __devinit mpc_i2c_setclock_8xxx(struct device_node *node, struct mpc_i2c *i2c, u32 clock, u32 prescaler) { int ret, fdr; ret = mpc_i2c_get_fdr_8xxx(node, clock, prescaler); fdr = (ret >= 0) ? ret : 0x1031; /* backward compatibility */ writeb(fdr & 0xff, i2c->base + MPC_I2C_FDR); writeb((fdr >> 8) & 0xff, i2c->base + MPC_I2C_DFSRR); if (ret >= 0) dev_info(i2c->dev, "clock %d Hz (dfsrr=%d fdr=%d)\n", clock, fdr >> 8, fdr & 0xff); } #else /* !CONFIG_FSL_SOC */ static void __devinit mpc_i2c_setclock_8xxx(struct device_node *node, struct mpc_i2c *i2c, u32 clock, u32 prescaler) { } #endif /* CONFIG_FSL_SOC */ static void mpc_i2c_start(struct mpc_i2c *i2c) { /* Clear arbitration */ writeb(0, i2c->base + MPC_I2C_SR); /* Start with MEN */ writeccr(i2c, CCR_MEN); } static void mpc_i2c_stop(struct mpc_i2c *i2c) { writeccr(i2c, CCR_MEN); } static int mpc_write(struct mpc_i2c *i2c, int target, const u8 *data, int length, int restart) { int i, result; unsigned timeout = i2c->adap.timeout; u32 flags = restart ? CCR_RSTA : 0; /* Start as master */ writeccr(i2c, CCR_MIEN | CCR_MEN | CCR_MSTA | CCR_MTX | flags); /* Write target byte */ writeb((target << 1), i2c->base + MPC_I2C_DR); result = i2c_wait(i2c, timeout, 1); if (result < 0) return result; for (i = 0; i < length; i++) { /* Write data byte */ writeb(data[i], i2c->base + MPC_I2C_DR); result = i2c_wait(i2c, timeout, 1); if (result < 0) return result; } return 0; } static int mpc_read(struct mpc_i2c *i2c, int target, u8 *data, int length, int restart) { unsigned timeout = i2c->adap.timeout; int i, result; u32 flags = restart ? CCR_RSTA : 0; /* Switch to read - restart */ writeccr(i2c, CCR_MIEN | CCR_MEN | CCR_MSTA | CCR_MTX | flags); /* Write target address byte - this time with the read flag set */ writeb((target << 1) | 1, i2c->base + MPC_I2C_DR); result = i2c_wait(i2c, timeout, 1); if (result < 0) return result; if (length) { if (length == 1) writeccr(i2c, CCR_MIEN | CCR_MEN | CCR_MSTA | CCR_TXAK); else writeccr(i2c, CCR_MIEN | CCR_MEN | CCR_MSTA); /* Dummy read */ readb(i2c->base + MPC_I2C_DR); } for (i = 0; i < length; i++) { 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); } return length; } static int mpc_xfer(struct i2c_adapter *adap, struct i2c_msg *msgs, int num) { struct i2c_msg *pmsg; int i; int ret = 0; unsigned long orig_jiffies = jiffies; struct mpc_i2c *i2c = i2c_get_adapdata(adap); mpc_i2c_start(i2c); /* Allow bus up to 1s to become not busy */ while (readb(i2c->base + MPC_I2C_SR) & CSR_MBB) { if (signal_pending(current)) { dev_dbg(i2c->dev, "Interrupted\n"); writeccr(i2c, 0); return -EINTR; } if (time_after(jiffies, orig_jiffies + HZ)) { dev_dbg(i2c->dev, "timeout\n"); if (readb(i2c->base + MPC_I2C_SR) == (CSR_MCF | CSR_MBB | CSR_RXAK)) mpc_i2c_fixup(i2c); return -EIO; } schedule(); } for (i = 0; ret >= 0 && i < num; i++) { pmsg = &msgs[i]; dev_dbg(i2c->dev, "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 ret = mpc_write(i2c, pmsg->addr, pmsg->buf, pmsg->len, i); } 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; } static const struct i2c_algorithm mpc_algo = { .master_xfer = mpc_xfer, .functionality = mpc_functionality, }; static struct i2c_adapter mpc_ops = { .owner = THIS_MODULE, .name = "MPC adapter", .algo = &mpc_algo, .timeout = HZ, }; static int __devinit fsl_i2c_probe(struct of_device *op, const struct of_device_id *match) { struct mpc_i2c *i2c; const u32 *prop; u32 clock = 0; int result = 0; int plen; i2c = kzalloc(sizeof(*i2c), GFP_KERNEL); if (!i2c) return -ENOMEM; i2c->dev = &op->dev; /* for debug and error output */ init_waitqueue_head(&i2c->queue); i2c->base = of_iomap(op->node, 0); if (!i2c->base) { dev_err(i2c->dev, "failed to map controller\n"); result = -ENOMEM; goto fail_map; } i2c->irq = irq_of_parse_and_map(op->node, 0); if (i2c->irq != NO_IRQ) { /* i2c->irq = NO_IRQ implies polling */ result = request_irq(i2c->irq, mpc_i2c_isr, IRQF_SHARED, "i2c-mpc", i2c); if (result < 0) { dev_err(i2c->dev, "failed to attach interrupt\n"); goto fail_request; } } if (!of_get_property(op->node, "fsl,preserve-clocking", NULL)) { prop = of_get_property(op->node, "clock-frequency", &plen); if (prop && plen == sizeof(u32)) clock = *prop; if (match->data) { struct mpc_i2c_data *data = (struct mpc_i2c_data *)match->data; data->setclock(op->node, i2c, clock, data->prescaler); } else { /* Backwards compatibility */ if (of_get_property(op->node, "dfsrr", NULL)) mpc_i2c_setclock_8xxx(op->node, i2c, clock, 0); } } dev_set_drvdata(&op->dev, i2c); i2c->adap = mpc_ops; i2c_set_adapdata(&i2c->adap, i2c); i2c->adap.dev.parent = &op->dev; result = i2c_add_adapter(&i2c->adap); if (result < 0) { dev_err(i2c->dev, "failed to add adapter\n"); goto fail_add; } of_register_i2c_devices(&i2c->adap, op->node); return result; fail_add: dev_set_drvdata(&op->dev, NULL); free_irq(i2c->irq, i2c); fail_request: irq_dispose_mapping(i2c->irq); iounmap(i2c->base); fail_map: kfree(i2c); return result; }; static int __devexit fsl_i2c_remove(struct of_device *op) { struct mpc_i2c *i2c = dev_get_drvdata(&op->dev); i2c_del_adapter(&i2c->adap); dev_set_drvdata(&op->dev, NULL); if (i2c->irq != NO_IRQ) free_irq(i2c->irq, i2c); irq_dispose_mapping(i2c->irq); iounmap(i2c->base); kfree(i2c); return 0; }; static struct mpc_i2c_data mpc_i2c_data_52xx __devinitdata = { .setclock = mpc_i2c_setclock_52xx, }; static struct mpc_i2c_data mpc_i2c_data_8313 __devinitdata = { .setclock = mpc_i2c_setclock_8xxx, }; static struct mpc_i2c_data mpc_i2c_data_8543 __devinitdata = { .setclock = mpc_i2c_setclock_8xxx, .prescaler = 2, }; static struct mpc_i2c_data mpc_i2c_data_8544 __devinitdata = { .setclock = mpc_i2c_setclock_8xxx, .prescaler = 3, }; static const struct of_device_id mpc_i2c_of_match[] = { {.compatible = "mpc5200-i2c", .data = &mpc_i2c_data_52xx, }, {.compatible = "fsl,mpc5200b-i2c", .data = &mpc_i2c_data_52xx, }, {.compatible = "fsl,mpc5200-i2c", .data = &mpc_i2c_data_52xx, }, {.compatible = "fsl,mpc8313-i2c", .data = &mpc_i2c_data_8313, }, {.compatible = "fsl,mpc8543-i2c", .data = &mpc_i2c_data_8543, }, {.compatible = "fsl,mpc8544-i2c", .data = &mpc_i2c_data_8544, }, /* Backward compatibility */ {.compatible = "fsl-i2c", }, {}, }; MODULE_DEVICE_TABLE(of, mpc_i2c_of_match); /* Structure for a device driver */ static struct of_platform_driver mpc_i2c_driver = { .match_table = mpc_i2c_of_match, .probe = fsl_i2c_probe, .remove = __devexit_p(fsl_i2c_remove), .driver = { .owner = THIS_MODULE, .name = DRV_NAME, }, }; static int __init fsl_i2c_init(void) { int rv; rv = of_register_platform_driver(&mpc_i2c_driver); if (rv) printk(KERN_ERR DRV_NAME " of_register_platform_driver failed (%i)\n", rv); return rv; } static void __exit fsl_i2c_exit(void) { of_unregister_platform_driver(&mpc_i2c_driver); } module_init(fsl_i2c_init); module_exit(fsl_i2c_exit); MODULE_AUTHOR("Adrian Cox "); MODULE_DESCRIPTION("I2C-Bus adapter for MPC107 bridge and " "MPC824x/85xx/52xx processors"); MODULE_LICENSE("GPL");