/* * Support for the OLPC DCON and OLPC EC access * * Copyright © 2006 Advanced Micro Devices, Inc. * Copyright © 2007-2008 Andres Salomon * * 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. */ #include #include #include #include #include #include #include #include #include #include #include #include #include #include struct olpc_platform_t olpc_platform_info; EXPORT_SYMBOL_GPL(olpc_platform_info); static DEFINE_SPINLOCK(ec_lock); /* EC event mask to be applied during suspend (defining wakeup sources). */ static u16 ec_wakeup_mask; /* what the timeout *should* be (in ms) */ #define EC_BASE_TIMEOUT 20 /* the timeout that bugs in the EC might force us to actually use */ static int ec_timeout = EC_BASE_TIMEOUT; static int __init olpc_ec_timeout_set(char *str) { if (get_option(&str, &ec_timeout) != 1) { ec_timeout = EC_BASE_TIMEOUT; printk(KERN_ERR "olpc-ec: invalid argument to " "'olpc_ec_timeout=', ignoring!\n"); } printk(KERN_DEBUG "olpc-ec: using %d ms delay for EC commands.\n", ec_timeout); return 1; } __setup("olpc_ec_timeout=", olpc_ec_timeout_set); /* * These {i,o}bf_status functions return whether the buffers are full or not. */ static inline unsigned int ibf_status(unsigned int port) { return !!(inb(port) & 0x02); } static inline unsigned int obf_status(unsigned int port) { return inb(port) & 0x01; } #define wait_on_ibf(p, d) __wait_on_ibf(__LINE__, (p), (d)) static int __wait_on_ibf(unsigned int line, unsigned int port, int desired) { unsigned int timeo; int state = ibf_status(port); for (timeo = ec_timeout; state != desired && timeo; timeo--) { mdelay(1); state = ibf_status(port); } if ((state == desired) && (ec_timeout > EC_BASE_TIMEOUT) && timeo < (ec_timeout - EC_BASE_TIMEOUT)) { printk(KERN_WARNING "olpc-ec: %d: waited %u ms for IBF!\n", line, ec_timeout - timeo); } return !(state == desired); } #define wait_on_obf(p, d) __wait_on_obf(__LINE__, (p), (d)) static int __wait_on_obf(unsigned int line, unsigned int port, int desired) { unsigned int timeo; int state = obf_status(port); for (timeo = ec_timeout; state != desired && timeo; timeo--) { mdelay(1); state = obf_status(port); } if ((state == desired) && (ec_timeout > EC_BASE_TIMEOUT) && timeo < (ec_timeout - EC_BASE_TIMEOUT)) { printk(KERN_WARNING "olpc-ec: %d: waited %u ms for OBF!\n", line, ec_timeout - timeo); } return !(state == desired); } /* * This allows the kernel to run Embedded Controller commands. The EC is * documented at , and the * available EC commands are here: * . Unfortunately, while * OpenFirmware's source is available, the EC's is not. */ int olpc_ec_cmd(unsigned char cmd, unsigned char *inbuf, size_t inlen, unsigned char *outbuf, size_t outlen) { unsigned long flags; int ret = -EIO; int i; int restarts = 0; spin_lock_irqsave(&ec_lock, flags); /* Clear OBF */ for (i = 0; i < 10 && (obf_status(0x6c) == 1); i++) inb(0x68); if (i == 10) { printk(KERN_ERR "olpc-ec: timeout while attempting to " "clear OBF flag!\n"); goto err; } if (wait_on_ibf(0x6c, 0)) { printk(KERN_ERR "olpc-ec: timeout waiting for EC to " "quiesce!\n"); goto err; } restart: /* * Note that if we time out during any IBF checks, that's a failure; * we have to return. There's no way for the kernel to clear that. * * If we time out during an OBF check, we can restart the command; * reissuing it will clear the OBF flag, and we should be alright. * The OBF flag will sometimes misbehave due to what we believe * is a hardware quirk.. */ pr_devel("olpc-ec: running cmd 0x%x\n", cmd); outb(cmd, 0x6c); if (wait_on_ibf(0x6c, 0)) { printk(KERN_ERR "olpc-ec: timeout waiting for EC to read " "command!\n"); goto err; } if (inbuf && inlen) { /* write data to EC */ for (i = 0; i < inlen; i++) { if (wait_on_ibf(0x6c, 0)) { printk(KERN_ERR "olpc-ec: timeout waiting for" " EC accept data!\n"); goto err; } pr_devel("olpc-ec: sending cmd arg 0x%x\n", inbuf[i]); outb(inbuf[i], 0x68); } } if (outbuf && outlen) { /* read data from EC */ for (i = 0; i < outlen; i++) { if (wait_on_obf(0x6c, 1)) { printk(KERN_ERR "olpc-ec: timeout waiting for" " EC to provide data!\n"); if (restarts++ < 10) goto restart; goto err; } outbuf[i] = inb(0x68); pr_devel("olpc-ec: received 0x%x\n", outbuf[i]); } } ret = 0; err: spin_unlock_irqrestore(&ec_lock, flags); return ret; } EXPORT_SYMBOL_GPL(olpc_ec_cmd); void olpc_ec_wakeup_set(u16 value) { ec_wakeup_mask |= value; } EXPORT_SYMBOL_GPL(olpc_ec_wakeup_set); void olpc_ec_wakeup_clear(u16 value) { ec_wakeup_mask &= ~value; } EXPORT_SYMBOL_GPL(olpc_ec_wakeup_clear); /* * Returns true if the compile and runtime configurations allow for EC events * to wake the system. */ bool olpc_ec_wakeup_available(void) { if (!machine_is_olpc()) return false; /* * XO-1 EC wakeups are available when olpc-xo1-sci driver is * compiled in */ #ifdef CONFIG_OLPC_XO1_SCI if (olpc_platform_info.boardrev < olpc_board_pre(0xd0)) /* XO-1 */ return true; #endif return false; } EXPORT_SYMBOL_GPL(olpc_ec_wakeup_available); int olpc_ec_mask_write(u16 bits) { if (olpc_platform_info.flags & OLPC_F_EC_WIDE_SCI) { __be16 ec_word = cpu_to_be16(bits); return olpc_ec_cmd(EC_WRITE_EXT_SCI_MASK, (void *) &ec_word, 2, NULL, 0); } else { unsigned char ec_byte = bits & 0xff; return olpc_ec_cmd(EC_WRITE_SCI_MASK, &ec_byte, 1, NULL, 0); } } EXPORT_SYMBOL_GPL(olpc_ec_mask_write); int olpc_ec_sci_query(u16 *sci_value) { int ret; if (olpc_platform_info.flags & OLPC_F_EC_WIDE_SCI) { __be16 ec_word; ret = olpc_ec_cmd(EC_EXT_SCI_QUERY, NULL, 0, (void *) &ec_word, 2); if (ret == 0) *sci_value = be16_to_cpu(ec_word); } else { unsigned char ec_byte; ret = olpc_ec_cmd(EC_SCI_QUERY, NULL, 0, &ec_byte, 1); if (ret == 0) *sci_value = ec_byte; } return ret; } EXPORT_SYMBOL_GPL(olpc_ec_sci_query); static int olpc_ec_suspend(void) { return olpc_ec_mask_write(ec_wakeup_mask); } static bool __init check_ofw_architecture(struct device_node *root) { const char *olpc_arch; int propsize; olpc_arch = of_get_property(root, "architecture", &propsize); return propsize == 5 && strncmp("OLPC", olpc_arch, 5) == 0; } static u32 __init get_board_revision(struct device_node *root) { int propsize; const __be32 *rev; rev = of_get_property(root, "board-revision-int", &propsize); if (propsize != 4) return 0; return be32_to_cpu(*rev); } static bool __init platform_detect(void) { struct device_node *root = of_find_node_by_path("/"); bool success; if (!root) return false; success = check_ofw_architecture(root); if (success) { olpc_platform_info.boardrev = get_board_revision(root); olpc_platform_info.flags |= OLPC_F_PRESENT; } of_node_put(root); return success; } static int __init add_xo1_platform_devices(void) { struct platform_device *pdev; pdev = platform_device_register_simple("xo1-rfkill", -1, NULL, 0); if (IS_ERR(pdev)) return PTR_ERR(pdev); pdev = platform_device_register_simple("olpc-xo1", -1, NULL, 0); if (IS_ERR(pdev)) return PTR_ERR(pdev); return 0; } static struct syscore_ops olpc_syscore_ops = { .suspend = olpc_ec_suspend, }; static int __init olpc_init(void) { int r = 0; if (!olpc_ofw_present() || !platform_detect()) return 0; spin_lock_init(&ec_lock); /* assume B1 and above models always have a DCON */ if (olpc_board_at_least(olpc_board(0xb1))) olpc_platform_info.flags |= OLPC_F_DCON; /* get the EC revision */ olpc_ec_cmd(EC_FIRMWARE_REV, NULL, 0, (unsigned char *) &olpc_platform_info.ecver, 1); #ifdef CONFIG_PCI_OLPC /* If the VSA exists let it emulate PCI, if not emulate in kernel. * XO-1 only. */ if (olpc_platform_info.boardrev < olpc_board_pre(0xd0) && !cs5535_has_vsa2()) x86_init.pci.arch_init = pci_olpc_init; #endif /* EC version 0x5f adds support for wide SCI mask */ if (olpc_platform_info.ecver >= 0x5f) olpc_platform_info.flags |= OLPC_F_EC_WIDE_SCI; printk(KERN_INFO "OLPC board revision %s%X (EC=%x)\n", ((olpc_platform_info.boardrev & 0xf) < 8) ? "pre" : "", olpc_platform_info.boardrev >> 4, olpc_platform_info.ecver); if (olpc_platform_info.boardrev < olpc_board_pre(0xd0)) { /* XO-1 */ r = add_xo1_platform_devices(); if (r) return r; } register_syscore_ops(&olpc_syscore_ops); return 0; } postcore_initcall(olpc_init);