spi: dw: Use regset32 DebugFS method to create regdump file

DebugFS kernel interface provides a dedicated method to create the
registers dump file. Use it instead of creating a generic DebugFS
file with manually written read callback function.

Signed-off-by: Serge Semin <Sergey.Semin@baikalelectronics.ru>
Reviewed-by: Andy Shevchenko <andriy.shevchenko@linux.intel.com>
Cc: Georgy Vlasov <Georgy.Vlasov@baikalelectronics.ru>
Cc: Ramil Zaripov <Ramil.Zaripov@baikalelectronics.ru>
Cc: Alexey Malahov <Alexey.Malahov@baikalelectronics.ru>
Cc: Thomas Bogendoerfer <tsbogend@alpha.franken.de>
Cc: Arnd Bergmann <arnd@arndb.de>
Cc: Feng Tang <feng.tang@intel.com>
Cc: Rob Herring <robh+dt@kernel.org>
Cc: linux-mips@vger.kernel.org
Cc: devicetree@vger.kernel.org
Link: https://lore.kernel.org/r/20200529131205.31838-16-Sergey.Semin@baikalelectronics.ru
Signed-off-by: Mark Brown <broonie@kernel.org>

diff --git a/drivers/spi/spi-dw-core.c b/drivers/spi/spi-dw-core.c
index 1f1a353..caeece6 100644 (file)
--- a/drivers/spi/spi-dw-core.c
+++ b/drivers/spi/spi-dw-core.c
@@ -29,66 +29,29 @@ struct chip_data {
 };
 
 #ifdef CONFIG_DEBUG_FS
-#define SPI_REGS_BUFSIZE       1024
-static ssize_t dw_spi_show_regs(struct file *file, char __user *user_buf,
-               size_t count, loff_t *ppos)
-{
-       struct dw_spi *dws = file->private_data;
-       char *buf;
-       u32 len = 0;
-       ssize_t ret;
-
-       buf = kzalloc(SPI_REGS_BUFSIZE, GFP_KERNEL);
-       if (!buf)
-               return 0;
-
-       len += scnprintf(buf + len, SPI_REGS_BUFSIZE - len,
-                       "%s registers:\n", dev_name(&dws->master->dev));
-       len += scnprintf(buf + len, SPI_REGS_BUFSIZE - len,
-                       "=================================\n");
-       len += scnprintf(buf + len, SPI_REGS_BUFSIZE - len,
-                       "CTRLR0: \t0x%08x\n", dw_readl(dws, DW_SPI_CTRLR0));
-       len += scnprintf(buf + len, SPI_REGS_BUFSIZE - len,
-                       "CTRLR1: \t0x%08x\n", dw_readl(dws, DW_SPI_CTRLR1));
-       len += scnprintf(buf + len, SPI_REGS_BUFSIZE - len,
-                       "SSIENR: \t0x%08x\n", dw_readl(dws, DW_SPI_SSIENR));
-       len += scnprintf(buf + len, SPI_REGS_BUFSIZE - len,
-                       "SER: \t\t0x%08x\n", dw_readl(dws, DW_SPI_SER));
-       len += scnprintf(buf + len, SPI_REGS_BUFSIZE - len,
-                       "BAUDR: \t\t0x%08x\n", dw_readl(dws, DW_SPI_BAUDR));
-       len += scnprintf(buf + len, SPI_REGS_BUFSIZE - len,
-                       "TXFTLR: \t0x%08x\n", dw_readl(dws, DW_SPI_TXFTLR));
-       len += scnprintf(buf + len, SPI_REGS_BUFSIZE - len,
-                       "RXFTLR: \t0x%08x\n", dw_readl(dws, DW_SPI_RXFTLR));
-       len += scnprintf(buf + len, SPI_REGS_BUFSIZE - len,
-                       "TXFLR: \t\t0x%08x\n", dw_readl(dws, DW_SPI_TXFLR));
-       len += scnprintf(buf + len, SPI_REGS_BUFSIZE - len,
-                       "RXFLR: \t\t0x%08x\n", dw_readl(dws, DW_SPI_RXFLR));
-       len += scnprintf(buf + len, SPI_REGS_BUFSIZE - len,
-                       "SR: \t\t0x%08x\n", dw_readl(dws, DW_SPI_SR));
-       len += scnprintf(buf + len, SPI_REGS_BUFSIZE - len,
-                       "IMR: \t\t0x%08x\n", dw_readl(dws, DW_SPI_IMR));
-       len += scnprintf(buf + len, SPI_REGS_BUFSIZE - len,
-                       "ISR: \t\t0x%08x\n", dw_readl(dws, DW_SPI_ISR));
-       len += scnprintf(buf + len, SPI_REGS_BUFSIZE - len,
-                       "DMACR: \t\t0x%08x\n", dw_readl(dws, DW_SPI_DMACR));
-       len += scnprintf(buf + len, SPI_REGS_BUFSIZE - len,
-                       "DMATDLR: \t0x%08x\n", dw_readl(dws, DW_SPI_DMATDLR));
-       len += scnprintf(buf + len, SPI_REGS_BUFSIZE - len,
-                       "DMARDLR: \t0x%08x\n", dw_readl(dws, DW_SPI_DMARDLR));
-       len += scnprintf(buf + len, SPI_REGS_BUFSIZE - len,
-                       "=================================\n");
-
-       ret = simple_read_from_buffer(user_buf, count, ppos, buf, len);
-       kfree(buf);
-       return ret;
+
+#define DW_SPI_DBGFS_REG(_name, _off)  \
+{                                      \
+       .name = _name,                  \
+       .offset = _off,                 \
 }
 
-static const struct file_operations dw_spi_regs_ops = {
-       .owner          = THIS_MODULE,
-       .open           = simple_open,
-       .read           = dw_spi_show_regs,
-       .llseek         = default_llseek,
+static const struct debugfs_reg32 dw_spi_dbgfs_regs[] = {
+       DW_SPI_DBGFS_REG("CTRLR0", DW_SPI_CTRLR0),
+       DW_SPI_DBGFS_REG("CTRLR1", DW_SPI_CTRLR1),
+       DW_SPI_DBGFS_REG("SSIENR", DW_SPI_SSIENR),
+       DW_SPI_DBGFS_REG("SER", DW_SPI_SER),
+       DW_SPI_DBGFS_REG("BAUDR", DW_SPI_BAUDR),
+       DW_SPI_DBGFS_REG("TXFTLR", DW_SPI_TXFTLR),
+       DW_SPI_DBGFS_REG("RXFTLR", DW_SPI_RXFTLR),
+       DW_SPI_DBGFS_REG("TXFLR", DW_SPI_TXFLR),
+       DW_SPI_DBGFS_REG("RXFLR", DW_SPI_RXFLR),
+       DW_SPI_DBGFS_REG("SR", DW_SPI_SR),
+       DW_SPI_DBGFS_REG("IMR", DW_SPI_IMR),
+       DW_SPI_DBGFS_REG("ISR", DW_SPI_ISR),
+       DW_SPI_DBGFS_REG("DMACR", DW_SPI_DMACR),
+       DW_SPI_DBGFS_REG("DMATDLR", DW_SPI_DMATDLR),
+       DW_SPI_DBGFS_REG("DMARDLR", DW_SPI_DMARDLR),
 };
 
 static int dw_spi_debugfs_init(struct dw_spi *dws)
@@ -100,8 +63,11 @@ static int dw_spi_debugfs_init(struct dw_spi *dws)
        if (!dws->debugfs)
                return -ENOMEM;
 
-       debugfs_create_file("registers", S_IFREG | S_IRUGO,
-               dws->debugfs, (void *)dws, &dw_spi_regs_ops);
+       dws->regset.regs = dw_spi_dbgfs_regs;
+       dws->regset.nregs = ARRAY_SIZE(dw_spi_dbgfs_regs);
+       dws->regset.base = dws->regs;
+       debugfs_create_regset32("registers", 0400, dws->debugfs, &dws->regset);
+
        return 0;
 }
 

diff --git a/drivers/spi/spi-dw.h b/drivers/spi/spi-dw.h
index 0b2cd79..151ba31 100644 (file)
--- a/drivers/spi/spi-dw.h
+++ b/drivers/spi/spi-dw.h
@@ -3,6 +3,7 @@
 #define DW_SPI_HEADER_H
 
 #include <linux/completion.h>
+#include <linux/debugfs.h>
 #include <linux/irqreturn.h>
 #include <linux/io.h>
 #include <linux/scatterlist.h>
@@ -152,6 +153,7 @@ struct dw_spi {
 
 #ifdef CONFIG_DEBUG_FS
        struct dentry *debugfs;
+       struct debugfs_regset32 regset;
 #endif
 };