// SPDX-License-Identifier: GPL-2.0-or-later /* * Support for the OLPC DCON and OLPC EC access * * Copyright © 2006 Advanced Micro Devices, Inc. * Copyright © 2007-2008 Andres Salomon */ #include #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); /* 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. */ static int olpc_xo1_ec_cmd(u8 cmd, u8 *inbuf, size_t inlen, u8 *outbuf, size_t outlen, void *arg) { int ret = -EIO; int i; int restarts = 0; /* 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++) { pr_devel("olpc-ec: sending cmd arg 0x%x\n", inbuf[i]); outb(inbuf[i], 0x68); if (wait_on_ibf(0x6c, 0)) { printk(KERN_ERR "olpc-ec: timeout waiting for" " EC accept data!\n"); goto err; } } } 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: return ret; } 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; pr_info("OLPC board revision %s%X\n", ((olpc_platform_info.boardrev & 0xf) < 8) ? "pre" : "", olpc_platform_info.boardrev >> 4); } 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); return PTR_ERR_OR_ZERO(pdev); } static int olpc_xo1_ec_suspend(struct platform_device *pdev) { /* * Squelch SCIs while suspended. This is a fix for * . */ return olpc_ec_cmd(EC_SET_SCI_INHIBIT, NULL, 0, NULL, 0); } static int olpc_xo1_ec_resume(struct platform_device *pdev) { /* Tell the EC to stop inhibiting SCIs */ olpc_ec_cmd(EC_SET_SCI_INHIBIT_RELEASE, NULL, 0, NULL, 0); /* * Tell the wireless module to restart USB communication. * Must be done twice. */ olpc_ec_cmd(EC_WAKE_UP_WLAN, NULL, 0, NULL, 0); olpc_ec_cmd(EC_WAKE_UP_WLAN, NULL, 0, NULL, 0); return 0; } static struct olpc_ec_driver ec_xo1_driver = { .suspend = olpc_xo1_ec_suspend, .resume = olpc_xo1_ec_resume, .ec_cmd = olpc_xo1_ec_cmd, #ifdef CONFIG_OLPC_XO1_SCI /* * XO-1 EC wakeups are available when olpc-xo1-sci driver is * compiled in */ .wakeup_available = true, #endif }; static struct olpc_ec_driver ec_xo1_5_driver = { .ec_cmd = olpc_xo1_ec_cmd, #ifdef CONFIG_OLPC_XO1_5_SCI /* * XO-1.5 EC wakeups are available when olpc-xo15-sci driver is * compiled in */ .wakeup_available = true, #endif }; static int __init olpc_init(void) { int r = 0; if (!olpc_ofw_present() || !platform_detect()) return 0; /* register the XO-1 and 1.5-specific EC handler */ if (olpc_platform_info.boardrev < olpc_board_pre(0xd0)) /* XO-1 */ olpc_ec_driver_register(&ec_xo1_driver, NULL); else olpc_ec_driver_register(&ec_xo1_5_driver, NULL); platform_device_register_simple("olpc-ec", -1, NULL, 0); /* assume B1 and above models always have a DCON */ if (olpc_board_at_least(olpc_board(0xb1))) olpc_platform_info.flags |= OLPC_F_DCON; #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 if (olpc_platform_info.boardrev < olpc_board_pre(0xd0)) { /* XO-1 */ r = add_xo1_platform_devices(); if (r) return r; } return 0; } postcore_initcall(olpc_init);