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authorLinus Torvalds <torvalds@linux-foundation.org>2014-12-19 21:57:45 +0100
committerLinus Torvalds <torvalds@linux-foundation.org>2014-12-19 21:57:45 +0100
commit34b85e3574424beb30e4cd163e6da2e2282d2683 (patch)
tree8962201bcfb406db85796f2690f92bcc051373f4 /drivers/i2c
parentUpdate/Remove soon-to-be-dead email address (diff)
parentpowerpc/powernv: Ignore smt-enabled on Power8 and later (diff)
downloadlinux-34b85e3574424beb30e4cd163e6da2e2282d2683.tar.xz
linux-34b85e3574424beb30e4cd163e6da2e2282d2683.zip
Merge tag 'powerpc-3.19-2' of git://git.kernel.org/pub/scm/linux/kernel/git/mpe/linux
Pull second batch of powerpc updates from Michael Ellerman: "The highlight is the series that reworks the idle management on powernv, which allows us to use deeper idle states on those machines. There's the fix from Anton for the "BUG at kernel/smpboot.c:134!" problem. An i2c driver for powernv. This is acked by Wolfram Sang, and he asked that we take it through the powerpc tree. A fix for audit from rgb at Red Hat, acked by Paul Moore who is one of the audit maintainers. A patch from Ben to export the symbol map of our OPAL firmware as a sysfs file, so that tools can use it. Also some CXL fixes, a couple of powerpc perf fixes, a fix for smt-enabled, and the patch to add __force to get_user() so we can use bitwise types" * tag 'powerpc-3.19-2' of git://git.kernel.org/pub/scm/linux/kernel/git/mpe/linux: powerpc/powernv: Ignore smt-enabled on Power8 and later powerpc/uaccess: Allow get_user() with bitwise types powerpc/powernv: Expose OPAL firmware symbol map powernv/powerpc: Add winkle support for offline cpus powernv/cpuidle: Redesign idle states management powerpc/powernv: Enable Offline CPUs to enter deep idle states powerpc/powernv: Switch off MMU before entering nap/sleep/rvwinkle mode i2c: Driver to expose PowerNV platform i2c busses powerpc: add little endian flag to syscall_get_arch() power/perf/hv-24x7: Use kmem_cache_free() instead of kfree powerpc/perf/hv-24x7: Use per-cpu page buffer cxl: Unmap MMIO regions when detaching a context cxl: Add timeout to process element commands cxl: Change contexts_lock to a mutex to fix sleep while atomic bug powerpc: Secondary CPUs must set cpu_callin_map after setting active and online
Diffstat (limited to 'drivers/i2c')
-rw-r--r--drivers/i2c/busses/Kconfig11
-rw-r--r--drivers/i2c/busses/Makefile1
-rw-r--r--drivers/i2c/busses/i2c-opal.c294
3 files changed, 306 insertions, 0 deletions
diff --git a/drivers/i2c/busses/Kconfig b/drivers/i2c/busses/Kconfig
index c1351d9fb35b..91a488c7cc44 100644
--- a/drivers/i2c/busses/Kconfig
+++ b/drivers/i2c/busses/Kconfig
@@ -1072,4 +1072,15 @@ config SCx200_ACB
This support is also available as a module. If so, the module
will be called scx200_acb.
+config I2C_OPAL
+ tristate "IBM OPAL I2C driver"
+ depends on PPC_POWERNV
+ default y
+ help
+ This exposes the PowerNV platform i2c busses to the linux i2c layer,
+ the driver is based on the OPAL interfaces.
+
+ This driver can also be built as a module. If so, the module will be
+ called as i2c-opal.
+
endmenu
diff --git a/drivers/i2c/busses/Makefile b/drivers/i2c/busses/Makefile
index 5e6c8223719e..56388f658d2f 100644
--- a/drivers/i2c/busses/Makefile
+++ b/drivers/i2c/busses/Makefile
@@ -102,6 +102,7 @@ obj-$(CONFIG_I2C_ACORN) += i2c-acorn.o
obj-$(CONFIG_I2C_BCM_KONA) += i2c-bcm-kona.o
obj-$(CONFIG_I2C_CROS_EC_TUNNEL) += i2c-cros-ec-tunnel.o
obj-$(CONFIG_I2C_ELEKTOR) += i2c-elektor.o
+obj-$(CONFIG_I2C_OPAL) += i2c-opal.o
obj-$(CONFIG_I2C_PCA_ISA) += i2c-pca-isa.o
obj-$(CONFIG_I2C_SIBYTE) += i2c-sibyte.o
obj-$(CONFIG_SCx200_ACB) += scx200_acb.o
diff --git a/drivers/i2c/busses/i2c-opal.c b/drivers/i2c/busses/i2c-opal.c
new file mode 100644
index 000000000000..16f90b1a7508
--- /dev/null
+++ b/drivers/i2c/busses/i2c-opal.c
@@ -0,0 +1,294 @@
+/*
+ * IBM OPAL I2C driver
+ * Copyright (C) 2014 IBM
+ *
+ * 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.
+ *
+ * This program is distributed in the hope that it will be useful,
+ * but WITHOUT ANY WARRANTY; without even the implied warranty of
+ * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the
+ * GNU General Public License for more details.
+ *
+ * You should have received a copy of the GNU General Public License
+ * along with this program.
+ */
+
+#include <linux/device.h>
+#include <linux/i2c.h>
+#include <linux/kernel.h>
+#include <linux/mm.h>
+#include <linux/module.h>
+#include <linux/of.h>
+#include <linux/platform_device.h>
+#include <linux/slab.h>
+
+#include <asm/firmware.h>
+#include <asm/opal.h>
+
+static int i2c_opal_translate_error(int rc)
+{
+ switch (rc) {
+ case OPAL_NO_MEM:
+ return -ENOMEM;
+ case OPAL_PARAMETER:
+ return -EINVAL;
+ case OPAL_I2C_ARBT_LOST:
+ return -EAGAIN;
+ case OPAL_I2C_TIMEOUT:
+ return -ETIMEDOUT;
+ case OPAL_I2C_NACK_RCVD:
+ return -ENXIO;
+ case OPAL_I2C_STOP_ERR:
+ return -EBUSY;
+ default:
+ return -EIO;
+ }
+}
+
+static int i2c_opal_send_request(u32 bus_id, struct opal_i2c_request *req)
+{
+ struct opal_msg msg;
+ int token, rc;
+
+ token = opal_async_get_token_interruptible();
+ if (token < 0) {
+ if (token != -ERESTARTSYS)
+ pr_err("Failed to get the async token\n");
+
+ return token;
+ }
+
+ rc = opal_i2c_request(token, bus_id, req);
+ if (rc != OPAL_ASYNC_COMPLETION) {
+ rc = i2c_opal_translate_error(rc);
+ goto exit;
+ }
+
+ rc = opal_async_wait_response(token, &msg);
+ if (rc)
+ goto exit;
+
+ rc = be64_to_cpu(msg.params[1]);
+ if (rc != OPAL_SUCCESS) {
+ rc = i2c_opal_translate_error(rc);
+ goto exit;
+ }
+
+exit:
+ opal_async_release_token(token);
+ return rc;
+}
+
+static int i2c_opal_master_xfer(struct i2c_adapter *adap, struct i2c_msg *msgs,
+ int num)
+{
+ unsigned long opal_id = (unsigned long)adap->algo_data;
+ struct opal_i2c_request req;
+ int rc, i;
+
+ /* We only support fairly simple combinations here of one
+ * or two messages
+ */
+ memset(&req, 0, sizeof(req));
+ switch(num) {
+ case 0:
+ return 0;
+ case 1:
+ req.type = (msgs[0].flags & I2C_M_RD) ?
+ OPAL_I2C_RAW_READ : OPAL_I2C_RAW_WRITE;
+ req.addr = cpu_to_be16(msgs[0].addr);
+ req.size = cpu_to_be32(msgs[0].len);
+ req.buffer_ra = cpu_to_be64(__pa(msgs[0].buf));
+ break;
+ case 2:
+ /* For two messages, we basically support only simple
+ * smbus transactions of a write plus a read. We might
+ * want to allow also two writes but we'd have to bounce
+ * the data into a single buffer.
+ */
+ if ((msgs[0].flags & I2C_M_RD) || !(msgs[1].flags & I2C_M_RD))
+ return -EOPNOTSUPP;
+ if (msgs[0].len > 4)
+ return -EOPNOTSUPP;
+ if (msgs[0].addr != msgs[1].addr)
+ return -EOPNOTSUPP;
+ req.type = OPAL_I2C_SM_READ;
+ req.addr = cpu_to_be16(msgs[0].addr);
+ req.subaddr_sz = msgs[0].len;
+ for (i = 0; i < msgs[0].len; i++)
+ req.subaddr = (req.subaddr << 8) | msgs[0].buf[i];
+ req.subaddr = cpu_to_be32(req.subaddr);
+ req.size = cpu_to_be32(msgs[1].len);
+ req.buffer_ra = cpu_to_be64(__pa(msgs[1].buf));
+ break;
+ default:
+ return -EOPNOTSUPP;
+ }
+
+ rc = i2c_opal_send_request(opal_id, &req);
+ if (rc)
+ return rc;
+
+ return num;
+}
+
+static int i2c_opal_smbus_xfer(struct i2c_adapter *adap, u16 addr,
+ unsigned short flags, char read_write,
+ u8 command, int size, union i2c_smbus_data *data)
+{
+ unsigned long opal_id = (unsigned long)adap->algo_data;
+ struct opal_i2c_request req;
+ u8 local[2];
+ int rc;
+
+ memset(&req, 0, sizeof(req));
+
+ req.addr = cpu_to_be16(addr);
+ switch (size) {
+ case I2C_SMBUS_BYTE:
+ req.buffer_ra = cpu_to_be64(__pa(&data->byte));
+ req.size = cpu_to_be32(1);
+ /* Fall through */
+ case I2C_SMBUS_QUICK:
+ req.type = (read_write == I2C_SMBUS_READ) ?
+ OPAL_I2C_RAW_READ : OPAL_I2C_RAW_WRITE;
+ break;
+ case I2C_SMBUS_BYTE_DATA:
+ req.buffer_ra = cpu_to_be64(__pa(&data->byte));
+ req.size = cpu_to_be32(1);
+ req.subaddr = cpu_to_be32(command);
+ req.subaddr_sz = 1;
+ req.type = (read_write == I2C_SMBUS_READ) ?
+ OPAL_I2C_SM_READ : OPAL_I2C_SM_WRITE;
+ break;
+ case I2C_SMBUS_WORD_DATA:
+ if (!read_write) {
+ local[0] = data->word & 0xff;
+ local[1] = (data->word >> 8) & 0xff;
+ }
+ req.buffer_ra = cpu_to_be64(__pa(local));
+ req.size = cpu_to_be32(2);
+ req.subaddr = cpu_to_be32(command);
+ req.subaddr_sz = 1;
+ req.type = (read_write == I2C_SMBUS_READ) ?
+ OPAL_I2C_SM_READ : OPAL_I2C_SM_WRITE;
+ break;
+ case I2C_SMBUS_I2C_BLOCK_DATA:
+ req.buffer_ra = cpu_to_be64(__pa(&data->block[1]));
+ req.size = cpu_to_be32(data->block[0]);
+ req.subaddr = cpu_to_be32(command);
+ req.subaddr_sz = 1;
+ req.type = (read_write == I2C_SMBUS_READ) ?
+ OPAL_I2C_SM_READ : OPAL_I2C_SM_WRITE;
+ break;
+ default:
+ return -EINVAL;
+ }
+
+ rc = i2c_opal_send_request(opal_id, &req);
+ if (!rc && read_write && size == I2C_SMBUS_WORD_DATA) {
+ data->word = ((u16)local[1]) << 8;
+ data->word |= local[0];
+ }
+
+ return rc;
+}
+
+static u32 i2c_opal_func(struct i2c_adapter *adapter)
+{
+ return I2C_FUNC_I2C | I2C_FUNC_SMBUS_QUICK | I2C_FUNC_SMBUS_BYTE |
+ I2C_FUNC_SMBUS_BYTE_DATA | I2C_FUNC_SMBUS_WORD_DATA |
+ I2C_FUNC_SMBUS_I2C_BLOCK;
+}
+
+static const struct i2c_algorithm i2c_opal_algo = {
+ .master_xfer = i2c_opal_master_xfer,
+ .smbus_xfer = i2c_opal_smbus_xfer,
+ .functionality = i2c_opal_func,
+};
+
+static int i2c_opal_probe(struct platform_device *pdev)
+{
+ struct i2c_adapter *adapter;
+ const char *pname;
+ u32 opal_id;
+ int rc;
+
+ if (!pdev->dev.of_node)
+ return -ENODEV;
+
+ rc = of_property_read_u32(pdev->dev.of_node, "ibm,opal-id", &opal_id);
+ if (rc) {
+ dev_err(&pdev->dev, "Missing ibm,opal-id property !\n");
+ return -EIO;
+ }
+
+ adapter = devm_kzalloc(&pdev->dev, sizeof(*adapter), GFP_KERNEL);
+ if (!adapter)
+ return -ENOMEM;
+
+ adapter->algo = &i2c_opal_algo;
+ adapter->algo_data = (void *)(unsigned long)opal_id;
+ adapter->dev.parent = &pdev->dev;
+ adapter->dev.of_node = of_node_get(pdev->dev.of_node);
+ pname = of_get_property(pdev->dev.of_node, "ibm,port-name", NULL);
+ if (pname)
+ strlcpy(adapter->name, pname, sizeof(adapter->name));
+ else
+ strlcpy(adapter->name, "opal", sizeof(adapter->name));
+
+ platform_set_drvdata(pdev, adapter);
+ rc = i2c_add_adapter(adapter);
+ if (rc)
+ dev_err(&pdev->dev, "Failed to register the i2c adapter\n");
+
+ return rc;
+}
+
+static int i2c_opal_remove(struct platform_device *pdev)
+{
+ struct i2c_adapter *adapter = platform_get_drvdata(pdev);
+
+ i2c_del_adapter(adapter);
+
+ return 0;
+}
+
+static const struct of_device_id i2c_opal_of_match[] = {
+ {
+ .compatible = "ibm,opal-i2c",
+ },
+ { }
+};
+MODULE_DEVICE_TABLE(of, i2c_opal_of_match);
+
+static struct platform_driver i2c_opal_driver = {
+ .probe = i2c_opal_probe,
+ .remove = i2c_opal_remove,
+ .driver = {
+ .name = "i2c-opal",
+ .of_match_table = i2c_opal_of_match,
+ },
+};
+
+static int __init i2c_opal_init(void)
+{
+ if (!firmware_has_feature(FW_FEATURE_OPAL))
+ return -ENODEV;
+
+ return platform_driver_register(&i2c_opal_driver);
+}
+module_init(i2c_opal_init);
+
+static void __exit i2c_opal_exit(void)
+{
+ return platform_driver_unregister(&i2c_opal_driver);
+}
+module_exit(i2c_opal_exit);
+
+MODULE_AUTHOR("Neelesh Gupta <neelegup@linux.vnet.ibm.com>");
+MODULE_DESCRIPTION("IBM OPAL I2C driver");
+MODULE_LICENSE("GPL");