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-rw-r--r--arch/x86/platform/olpc/olpc.c321
1 files changed, 321 insertions, 0 deletions
diff --git a/arch/x86/platform/olpc/olpc.c b/arch/x86/platform/olpc/olpc.c
new file mode 100644
index 000000000..1d4a00e76
--- /dev/null
+++ b/arch/x86/platform/olpc/olpc.c
@@ -0,0 +1,321 @@
+// 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 <dilinger@debian.org>
+ */
+
+#include <linux/kernel.h>
+#include <linux/init.h>
+#include <linux/export.h>
+#include <linux/delay.h>
+#include <linux/io.h>
+#include <linux/string.h>
+#include <linux/platform_device.h>
+#include <linux/of.h>
+#include <linux/syscore_ops.h>
+#include <linux/mutex.h>
+#include <linux/olpc-ec.h>
+
+#include <asm/geode.h>
+#include <asm/setup.h>
+#include <asm/olpc.h>
+#include <asm/olpc_ofw.h>
+
+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 <http://wiki.laptop.org/go/Embedded_controller>, and the
+ * available EC commands are here:
+ * <http://wiki.laptop.org/go/Ec_specification>. 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
+ * <http://dev.laptop.org/ticket/1835>.
+ */
+ 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_XO15_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);