[PATCH v5 5/5] ipmi: Convert DMI handling over to a platform device

From: minyard
Date: Wed May 17 2017 - 15:57:15 EST

From: Corey Minyard <cminyard@xxxxxxxxxx>

Now that the DMI code creates a platform device for IPMI devices
in the firmware, use that instead of handling all the DMI work
in the IPMI driver itself.

Signed-off-by: Corey Minyard <cminyard@xxxxxxxxxx>
Tested-by: Andy Lutomirski <luto@xxxxxxxxxx>
---
drivers/char/ipmi/ipmi_si_intf.c | 137 ++++++++-------------------------------
drivers/char/ipmi/ipmi_ssif.c | 119 ++++++++++++++++++++++------------
2 files changed, 106 insertions(+), 150 deletions(-)

diff --git a/drivers/char/ipmi/ipmi_si_intf.c b/drivers/char/ipmi/ipmi_si_intf.c
index b2b618f..17611a8 100644
--- a/drivers/char/ipmi/ipmi_si_intf.c
+++ b/drivers/char/ipmi/ipmi_si_intf.c
@@ -2274,121 +2274,45 @@ static void spmi_find_bmc(void)
#endif

#ifdef CONFIG_DMI
-struct dmi_ipmi_data {
- u8 type;
- u8 addr_space;
- unsigned long base_addr;
- u8 irq;
- u8 offset;
- u8 slave_addr;
-};
-
-static int decode_dmi(const struct dmi_header *dm,
- struct dmi_ipmi_data *dmi)
-{
- const u8 *data = (const u8 *)dm;
- unsigned long base_addr;
- u8 reg_spacing;
- u8 len = dm->length;
-
- dmi->type = data[4];
-
- memcpy(&base_addr, data+8, sizeof(unsigned long));
- if (len >= 0x11) {
- if (base_addr & 1) {
- /* I/O */
- base_addr &= 0xFFFE;
- dmi->addr_space = IPMI_IO_ADDR_SPACE;
- } else
- /* Memory */
- dmi->addr_space = IPMI_MEM_ADDR_SPACE;
-
- /* If bit 4 of byte 0x10 is set, then the lsb for the address
- is odd. */
- dmi->base_addr = base_addr | ((data[0x10] & 0x10) >> 4);
-
- dmi->irq = data[0x11];
-
- /* The top two bits of byte 0x10 hold the register spacing. */
- reg_spacing = (data[0x10] & 0xC0) >> 6;
- switch (reg_spacing) {
- case 0x00: /* Byte boundaries */
- dmi->offset = 1;
- break;
- case 0x01: /* 32-bit boundaries */
- dmi->offset = 4;
- break;
- case 0x02: /* 16-byte boundaries */
- dmi->offset = 16;
- break;
- default:
- /* Some other interface, just ignore it. */
- return -EIO;
- }
- } else {
- /* Old DMI spec. */
- /*
- * Note that technically, the lower bit of the base
- * address should be 1 if the address is I/O and 0 if
- * the address is in memory. So many systems get that
- * wrong (and all that I have seen are I/O) so we just
- * ignore that bit and assume I/O. Systems that use
- * memory should use the newer spec, anyway.
- */
- dmi->base_addr = base_addr & 0xfffe;
- dmi->addr_space = IPMI_IO_ADDR_SPACE;
- dmi->offset = 1;
- }
-
- dmi->slave_addr = data[6];
-
- return 0;
-}
-
-static void try_init_dmi(struct dmi_ipmi_data *ipmi_data)
+static int dmi_ipmi_probe(struct platform_device *pdev)
{
+ struct dmi_device *dmi_dev = to_dmi_device(pdev->dev.fwnode);
+ struct dmi_dev_ipmi *ipmi_data = to_dmi_dev_ipmi(dmi_dev);
struct smi_info *info;

+ if (!si_trydmi || !ipmi_data)
+ return -ENODEV;
+
info = smi_info_alloc();
if (!info) {
pr_err(PFX "Could not allocate SI data\n");
- return;
+ return -ENOMEM;
}

info->addr_source = SI_SMBIOS;
pr_info(PFX "probing via SMBIOS\n");

switch (ipmi_data->type) {
- case 0x01: /* KCS */
+ case IPMI_DMI_TYPE_KCS:
info->si_type = SI_KCS;
break;
- case 0x02: /* SMIC */
+ case IPMI_DMI_TYPE_SMIC:
info->si_type = SI_SMIC;
break;
- case 0x03: /* BT */
+ case IPMI_DMI_TYPE_BT:
info->si_type = SI_BT;
break;
default:
kfree(info);
- return;
+ return -EINVAL;
}

- switch (ipmi_data->addr_space) {
- case IPMI_MEM_ADDR_SPACE:
- info->io_setup = mem_setup;
- info->io.addr_type = IPMI_MEM_ADDR_SPACE;
- break;
-
- case IPMI_IO_ADDR_SPACE:
+ if (ipmi_data->is_io_space) {
info->io_setup = port_setup;
info->io.addr_type = IPMI_IO_ADDR_SPACE;
- break;
-
- default:
- kfree(info);
- pr_warn(PFX "Unknown SMBIOS I/O Address type: %d\n",
- ipmi_data->addr_space);
- return;
+ } else {
+ info->io_setup = mem_setup;
+ info->io.addr_type = IPMI_MEM_ADDR_SPACE;
}
info->io.addr_data = ipmi_data->base_addr;

@@ -2404,6 +2328,8 @@ static void try_init_dmi(struct dmi_ipmi_data *ipmi_data)
if (info->irq)
info->irq_setup = std_irq_setup;

+ info->dev = &pdev->dev;
+
pr_info("ipmi_si: SMBIOS: %s %#lx regsize %d spacing %d irq %d\n",
(info->io.addr_type == IPMI_IO_ADDR_SPACE) ? "io" : "mem",
info->io.addr_data, info->io.regsize, info->io.regspacing,
@@ -2411,21 +2337,13 @@ static void try_init_dmi(struct dmi_ipmi_data *ipmi_data)

if (add_smi(info))
kfree(info);
-}

-static void dmi_find_bmc(void)
+ return 0;
+}
+#else
+static int dmi_ipmi_probe(struct platform_device *pdev)
{
- const struct dmi_device *dev = NULL;
- struct dmi_ipmi_data data;
- int rv;
-
- while ((dev = dmi_find_device(DMI_DEV_TYPE_IPMI, NULL, dev))) {
- memset(&data, 0, sizeof(data));
- rv = decode_dmi((const struct dmi_header *) dev->device_data,
- &data);
- if (!rv)
- try_init_dmi(&data);
- }
+ return -ENODEV;
}
#endif /* CONFIG_DMI */

@@ -2813,7 +2731,10 @@ static int ipmi_probe(struct platform_device *dev)
if (of_ipmi_probe(dev) == 0)
return 0;

- return acpi_ipmi_probe(dev);
+ if (acpi_ipmi_probe(dev) == 0)
+ return 0;
+
+ return dmi_ipmi_probe(dev);
}

static int ipmi_remove(struct platform_device *dev)
@@ -3786,11 +3707,6 @@ static int init_ipmi_si(void)
}
#endif

-#ifdef CONFIG_DMI
- if (si_trydmi)
- dmi_find_bmc();
-#endif
-
#ifdef CONFIG_ACPI
if (si_tryacpi)
spmi_find_bmc();
@@ -3938,6 +3854,7 @@ static void cleanup_ipmi_si(void)
}
module_exit(cleanup_ipmi_si);

+MODULE_ALIAS("platform:dmi-ipmi-si");
MODULE_LICENSE("GPL");
MODULE_AUTHOR("Corey Minyard <minyard@xxxxxxxxxx>");
MODULE_DESCRIPTION("Interface to the IPMI driver for the KCS, SMIC, and BT"
diff --git a/drivers/char/ipmi/ipmi_ssif.c b/drivers/char/ipmi/ipmi_ssif.c
index 1d4fd84..109ca4e 100644
--- a/drivers/char/ipmi/ipmi_ssif.c
+++ b/drivers/char/ipmi/ipmi_ssif.c
@@ -180,6 +180,8 @@ struct ssif_addr_info {
int slave_addr;
enum ipmi_addr_src addr_src;
union ipmi_smi_info_union addr_info;
+ struct device *dev;
+ struct i2c_client *client;

struct mutex clients_mutex;
struct list_head clients;
@@ -1469,6 +1471,7 @@ static int ssif_probe(struct i2c_client *client, const struct i2c_device_id *id)
ssif_info->addr_source = addr_info->addr_src;
ssif_info->ssif_debug = addr_info->debug;
ssif_info->addr_info = addr_info->addr_info;
+ addr_info->client = client;
slave_addr = addr_info->slave_addr;
}
}
@@ -1706,8 +1709,19 @@ static int ssif_probe(struct i2c_client *client, const struct i2c_device_id *id)
}

out:
- if (rv)
+ if (rv) {
+ /*
+ * Note that if addr_info->client is assigned, we
+ * leave it. The i2c client hangs around even if we
+ * return a failure here, and the failure here is not
+ * propagated back to the i2c code. This seems to be
+ * design intent, strange as it may be. But if we
+ * don't leave it, ssif_platform_remove will not remove
+ * the client like it should.
+ */
+ dev_err(&client->dev, "Unable to start IPMI SSIF: %d\n", rv);
kfree(ssif_info);
+ }
kfree(resp);
return rv;

@@ -1732,7 +1746,8 @@ static int ssif_adapter_handler(struct device *adev, void *opaque)

static int new_ssif_client(int addr, char *adapter_name,
int debug, int slave_addr,
- enum ipmi_addr_src addr_src)
+ enum ipmi_addr_src addr_src,
+ struct device *dev)
{
struct ssif_addr_info *addr_info;
int rv = 0;
@@ -1762,9 +1777,14 @@ static int new_ssif_client(int addr, char *adapter_name,
sizeof(addr_info->binfo.type));
addr_info->binfo.addr = addr;
addr_info->binfo.platform_data = addr_info;
+ if (dev)
+ addr_info->binfo.fwnode = dev->fwnode;
addr_info->debug = debug;
addr_info->slave_addr = slave_addr;
addr_info->addr_src = addr_src;
+ addr_info->dev = dev;
+
+ dev_set_drvdata(dev, addr_info);

list_add_tail(&addr_info->link, &ssif_infos);

@@ -1903,7 +1923,7 @@ static int try_init_spmi(struct SPMITable *spmi)

myaddr = spmi->addr.address & 0x7f;

- return new_ssif_client(myaddr, NULL, 0, 0, SI_SPMI);
+ return new_ssif_client(myaddr, NULL, 0, 0, SI_SPMI, NULL);
}

static void spmi_find_bmc(void)
@@ -1932,48 +1952,30 @@ static void spmi_find_bmc(void) { }
#endif

#ifdef CONFIG_DMI
-static int decode_dmi(const struct dmi_device *dmi_dev)
+static int dmi_ipmi_probe(struct platform_device *pdev)
{
- struct dmi_header *dm = dmi_dev->device_data;
- u8 *data = (u8 *) dm;
- u8 len = dm->length;
- unsigned short myaddr;
- int slave_addr;
-
- if (num_addrs >= MAX_SSIF_BMCS)
- return -1;
+ struct dmi_device *dmi_dev = to_dmi_device(pdev->dev.fwnode);
+ struct dmi_dev_ipmi *ipmi_data = to_dmi_dev_ipmi(dmi_dev);

- if (len < 9)
- return -1;
-
- if (data[0x04] != 4) /* Not SSIF */
- return -1;
+ if (!ssif_trydmi || !ipmi_data)
+ return -ENODEV;

- if ((data[8] >> 1) == 0) {
- /*
- * Some broken systems put the I2C address in
- * the slave address field. We try to
- * accommodate them here.
- */
- myaddr = data[6] >> 1;
- slave_addr = 0;
- } else {
- myaddr = data[8] >> 1;
- slave_addr = data[6];
+ if (!ipmi_data->good_data) {
+ pr_err(PFX "DMI data for this device was invalid.\n");
+ return -EINVAL;
}

- return new_ssif_client(myaddr, NULL, 0, slave_addr, SI_SMBIOS);
-}
-
-static void dmi_iterator(void)
-{
- const struct dmi_device *dev = NULL;
+ if (ipmi_data->type != IPMI_DMI_TYPE_SSIF)
+ return -ENODEV;

- while ((dev = dmi_find_device(DMI_DEV_TYPE_IPMI, NULL, dev)))
- decode_dmi(dev);
+ return new_ssif_client(ipmi_data->base_addr, NULL, 0,
+ ipmi_data->slave_addr, SI_SMBIOS, &pdev->dev);
}
#else
-static void dmi_iterator(void) { }
+static int dmi_ipmi_probe(struct platform_device *pdev)
+{
+ return -ENODEV;
+}
#endif

static const struct i2c_device_id ssif_id[] = {
@@ -1994,6 +1996,36 @@ static struct i2c_driver ssif_i2c_driver = {
.detect = ssif_detect
};

+static int ssif_platform_probe(struct platform_device *dev)
+{
+ return dmi_ipmi_probe(dev);
+}
+
+static int ssif_platform_remove(struct platform_device *dev)
+{
+ struct ssif_addr_info *addr_info = dev_get_drvdata(&dev->dev);
+
+ if (!addr_info)
+ return 0;
+
+ mutex_lock(&ssif_infos_mutex);
+ if (addr_info->client)
+ i2c_unregister_device(addr_info->client);
+
+ list_del(&addr_info->link);
+ kfree(addr_info);
+ mutex_unlock(&ssif_infos_mutex);
+ return 0;
+}
+
+static struct platform_driver ipmi_driver = {
+ .driver = {
+ .name = DEVICE_NAME,
+ },
+ .probe = ssif_platform_probe,
+ .remove = ssif_platform_remove,
+};
+
static int init_ipmi_ssif(void)
{
int i;
@@ -2008,7 +2040,7 @@ static int init_ipmi_ssif(void)
for (i = 0; i < num_addrs; i++) {
rv = new_ssif_client(addr[i], adapter_name[i],
dbg[i], slave_addrs[i],
- SI_HARDCODED);
+ SI_HARDCODED, NULL);
if (rv)
pr_err(PFX
"Couldn't add hardcoded device at addr 0x%x\n",
@@ -2018,8 +2050,7 @@ static int init_ipmi_ssif(void)
if (ssif_tryacpi)
ssif_i2c_driver.driver.acpi_match_table =
ACPI_PTR(ssif_acpi_match);
- if (ssif_trydmi)
- dmi_iterator();
+
if (ssif_tryacpi)
spmi_find_bmc();

@@ -2029,6 +2060,11 @@ static int init_ipmi_ssif(void)
if (!rv)
initialized = true;

+ /* Wait until here so ACPI devices will start first. */
+ rv = platform_driver_register(&ipmi_driver);
+ if (rv)
+ pr_err(PFX "Unable to register driver: %d\n", rv);
+
return rv;
}
module_init(init_ipmi_ssif);
@@ -2040,12 +2076,15 @@ static void cleanup_ipmi_ssif(void)

initialized = false;

+ platform_driver_unregister(&ipmi_driver);
+
i2c_del_driver(&ssif_i2c_driver);

free_ssif_clients();
}
module_exit(cleanup_ipmi_ssif);

+MODULE_ALIAS("platform:dmi-ipmi-ssif");
MODULE_AUTHOR("Todd C Davis <todd.c.davis@xxxxxxxxx>, Corey Minyard <minyard@xxxxxxx>");
MODULE_DESCRIPTION("IPMI driver for management controllers on a SMBus");
MODULE_LICENSE("GPL");
--
2.7.4