diff mbox series

[v5,2/7] hwmon: pmbus: adm1266: Add Block process call

Message ID 20200624151736.95785-3-alexandru.tachici@analog.com (mailing list archive)
State Changes Requested
Headers show
Series hwmon: pmbus: adm1266: add support | expand

Commit Message

Alexandru Tachici June 24, 2020, 3:17 p.m. UTC 
From: Alexandru Tachici <alexandru.tachici@analog.com>

PmBus devices support Block Write-Block Read Process
Call described in SMBus specification v 2.0 with the
exception that Block writes and reads are permitted to
have up 255 data bytes instead of max 32 bytes (SMBus).

This patch adds Block WR process call support for ADM1266.

Signed-off-by: Alexandru Tachici <alexandru.tachici@analog.com>
---
 drivers/hwmon/pmbus/Kconfig   |  1 +
 drivers/hwmon/pmbus/adm1266.c | 79 +++++++++++++++++++++++++++++++++++
 2 files changed, 80 insertions(+)

Comments

kernel test robot June 24, 2020, 5 p.m. UTC | #1 
Hi,

I love your patch! Perhaps something to improve:

[auto build test WARNING on hwmon/hwmon-next]
[also build test WARNING on linux/master robh/for-next linus/master v5.8-rc2 next-20200624]
[If your patch is applied to the wrong git tree, kindly drop us a note.
And when submitting patch, we suggest to use  as documented in
https://git-scm.com/docs/git-format-patch]

url:    https://github.com/0day-ci/linux/commits/alexandru-tachici-analog-com/hwmon-pmbus-adm1266-add-support/20200624-232203
base:   https://git.kernel.org/pub/scm/linux/kernel/git/groeck/linux-staging.git hwmon-next
config: mips-allyesconfig (attached as .config)
compiler: mips-linux-gcc (GCC) 9.3.0
reproduce (this is a W=1 build):
        wget https://raw.githubusercontent.com/intel/lkp-tests/master/sbin/make.cross -O ~/bin/make.cross
        chmod +x ~/bin/make.cross
        # save the attached .config to linux build tree
        COMPILER_INSTALL_PATH=$HOME/0day COMPILER=gcc-9.3.0 make.cross ARCH=mips 

If you fix the issue, kindly add following tag as appropriate
Reported-by: kernel test robot <lkp@intel.com>

All warnings (new ones prefixed by >>):

>> drivers/hwmon/pmbus/adm1266.c:27:5: warning: no previous prototype for 'pmbus_block_xfer' [-Wmissing-prototypes]
      27 | int pmbus_block_xfer(struct i2c_client *client, u8 cmd, u8 w_len,
         |     ^~~~~~~~~~~~~~~~

vim +/pmbus_block_xfer +27 drivers/hwmon/pmbus/adm1266.c

    21	
    22	/* Different from Block Read as it sends data and waits for the slave to
    23	 * return a value dependent on that data. The protocol is simply a Write Block
    24	 * followed by a Read Block without the Read-Block command field and the
    25	 * Write-Block STOP bit.
    26	 */
  > 27	int pmbus_block_xfer(struct i2c_client *client, u8 cmd, u8 w_len,
    28			     u8 *data_w, u8 *data_r)
    29	{
    30		u8 write_buf[ADM1266_PMBUS_BLOCK_MAX + 2];
    31		struct i2c_msg msgs[2] = {
    32			{
    33				.addr = client->addr,
    34				.flags = 0,
    35				.buf = write_buf,
    36				.len = w_len + 2,
    37			},
    38			{
    39				.addr = client->addr,
    40				.flags = I2C_M_RD,
    41				.len = ADM1266_PMBUS_BLOCK_MAX + 2,
    42			}
    43		};
    44		u8 addr = 0;
    45		u8 crc = 0;
    46		int ret;
    47	
    48		msgs[0].buf[0] = cmd;
    49		msgs[0].buf[1] = w_len;
    50		memcpy(&msgs[0].buf[2], data_w, w_len);
    51	
    52		msgs[0].buf = i2c_get_dma_safe_msg_buf(&msgs[0], 1);
    53		if (!msgs[0].buf)
    54			return -ENOMEM;
    55	
    56		msgs[1].buf = i2c_get_dma_safe_msg_buf(&msgs[1], 1);
    57		if (!msgs[1].buf) {
    58			i2c_put_dma_safe_msg_buf(msgs[0].buf, &msgs[0], false);
    59			return -ENOMEM;
    60		}
    61	
    62		ret = i2c_transfer(client->adapter, msgs, 2);
    63		if (ret != 2) {
    64			ret = -EPROTO;
    65			goto cleanup;
    66		}
    67	
    68		if (client->flags & I2C_CLIENT_PEC) {
    69			addr = i2c_8bit_addr_from_msg(&msgs[0]);
    70			crc = crc8(pmbus_crc_table, &addr, 1, crc);
    71			crc = crc8(pmbus_crc_table, msgs[0].buf,  msgs[0].len, crc);
    72	
    73			addr = i2c_8bit_addr_from_msg(&msgs[1]);
    74			crc = crc8(pmbus_crc_table, &addr, 1, crc);
    75			crc = crc8(pmbus_crc_table, msgs[1].buf,  msgs[1].buf[0] + 1,
    76				   crc);
    77	
    78			if (crc != msgs[1].buf[msgs[1].buf[0] + 1]) {
    79				ret = -EBADMSG;
    80				goto cleanup;
    81			}
    82		}
    83	
    84		memcpy(data_r, &msgs[1].buf[1], msgs[1].buf[0]);
    85		ret = msgs[1].buf[0];
    86	
    87	cleanup:
    88		i2c_put_dma_safe_msg_buf(msgs[0].buf, &msgs[0], true);
    89		i2c_put_dma_safe_msg_buf(msgs[1].buf, &msgs[1], true);
    90	
    91		return ret;
    92	}
    93	

---
0-DAY CI Kernel Test Service, Intel Corporation
https://lists.01.org/hyperkitty/list/kbuild-all@lists.01.org
diff mbox series

Patch

diff --git a/drivers/hwmon/pmbus/Kconfig b/drivers/hwmon/pmbus/Kconfig
index da34083e1ffd..c04068b665e6 100644
--- a/drivers/hwmon/pmbus/Kconfig
+++ b/drivers/hwmon/pmbus/Kconfig
@@ -28,6 +28,7 @@  config SENSORS_PMBUS
 
 config SENSORS_ADM1266
 	tristate "Analog Devices ADM1266 Sequencer"
+	select CRC8
 	help
 	  If you say yes here you get hardware monitoring support for Analog
 	  Devices ADM1266 Cascadable Super Sequencer.
diff --git a/drivers/hwmon/pmbus/adm1266.c b/drivers/hwmon/pmbus/adm1266.c
index a7ef048a9a5c..381d89a8569f 100644
--- a/drivers/hwmon/pmbus/adm1266.c
+++ b/drivers/hwmon/pmbus/adm1266.c
@@ -6,6 +6,7 @@ 
  * Copyright 2020 Analog Devices Inc.
  */
 
+#include <linux/crc8.h>
 #include <linux/i2c.h>
 #include <linux/init.h>
 #include <linux/kernel.h>
@@ -14,6 +15,82 @@ 
 
 #include "pmbus.h"
 
+#define ADM1266_PMBUS_BLOCK_MAX		255
+
+DECLARE_CRC8_TABLE(pmbus_crc_table);
+
+/* Different from Block Read as it sends data and waits for the slave to
+ * return a value dependent on that data. The protocol is simply a Write Block
+ * followed by a Read Block without the Read-Block command field and the
+ * Write-Block STOP bit.
+ */
+int pmbus_block_xfer(struct i2c_client *client, u8 cmd, u8 w_len,
+		     u8 *data_w, u8 *data_r)
+{
+	u8 write_buf[ADM1266_PMBUS_BLOCK_MAX + 2];
+	struct i2c_msg msgs[2] = {
+		{
+			.addr = client->addr,
+			.flags = 0,
+			.buf = write_buf,
+			.len = w_len + 2,
+		},
+		{
+			.addr = client->addr,
+			.flags = I2C_M_RD,
+			.len = ADM1266_PMBUS_BLOCK_MAX + 2,
+		}
+	};
+	u8 addr = 0;
+	u8 crc = 0;
+	int ret;
+
+	msgs[0].buf[0] = cmd;
+	msgs[0].buf[1] = w_len;
+	memcpy(&msgs[0].buf[2], data_w, w_len);
+
+	msgs[0].buf = i2c_get_dma_safe_msg_buf(&msgs[0], 1);
+	if (!msgs[0].buf)
+		return -ENOMEM;
+
+	msgs[1].buf = i2c_get_dma_safe_msg_buf(&msgs[1], 1);
+	if (!msgs[1].buf) {
+		i2c_put_dma_safe_msg_buf(msgs[0].buf, &msgs[0], false);
+		return -ENOMEM;
+	}
+
+	ret = i2c_transfer(client->adapter, msgs, 2);
+	if (ret != 2) {
+		ret = -EPROTO;
+		goto cleanup;
+	}
+
+	if (client->flags & I2C_CLIENT_PEC) {
+		addr = i2c_8bit_addr_from_msg(&msgs[0]);
+		crc = crc8(pmbus_crc_table, &addr, 1, crc);
+		crc = crc8(pmbus_crc_table, msgs[0].buf,  msgs[0].len, crc);
+
+		addr = i2c_8bit_addr_from_msg(&msgs[1]);
+		crc = crc8(pmbus_crc_table, &addr, 1, crc);
+		crc = crc8(pmbus_crc_table, msgs[1].buf,  msgs[1].buf[0] + 1,
+			   crc);
+
+		if (crc != msgs[1].buf[msgs[1].buf[0] + 1]) {
+			ret = -EBADMSG;
+			goto cleanup;
+		}
+	}
+
+	memcpy(data_r, &msgs[1].buf[1], msgs[1].buf[0]);
+	ret = msgs[1].buf[0];
+
+cleanup:
+	i2c_put_dma_safe_msg_buf(msgs[0].buf, &msgs[0], true);
+	i2c_put_dma_safe_msg_buf(msgs[1].buf, &msgs[1], true);
+
+	return ret;
+}
+
 static int adm1266_probe(struct i2c_client *client,
 			 const struct i2c_device_id *id)
 {
@@ -24,6 +101,8 @@  static int adm1266_probe(struct i2c_client *client,
 	info = devm_kzalloc(&client->dev, sizeof(struct pmbus_driver_info),
 			    GFP_KERNEL);
 
+	crc8_populate_msb(pmbus_crc_table, 0x7);
+
 	info->pages = 17;
 	info->format[PSC_VOLTAGE_OUT] = linear;
 	funcs = PMBUS_HAVE_VOUT | PMBUS_HAVE_STATUS_VOUT;