-----Original Message-----
From: Pavel Machek <pavel@denx.de>
Sent: 24 November 2020 09:38
To: Prabhakar Mahadev Lad <prabhakar.mahadev-lad.rj@bp.renesas.com>
Cc: cip-dev@lists.cip-project.org; Nobuhiro Iwamatsu <nobuhiro1.iwamatsu@toshiba.co.jp>; Pavel Machek
<pavel@denx.de>; Biju Das <biju.das.jz@bp.renesas.com>
Subject: Re: [PATCH 4.19.y-cip 0/2] Add sound support to R8A774E1 SoC

Hi!

This patch series adds sound support to Renesas R8A774E1 SoC.

All the patches have been cherry picked from Linux v5.10-rc5.

Thanks, applied and pushed out.

Best regards,
Pavel

--
DENX Software Engineering GmbH, Managing Director: Wolfgang Denk
HRB 165235 Munich, Office: Kirchenstr.5, D-82194 Groebenzell, Germany

-----Original Message-----
From: Pavel Machek <pavel@denx.de>
Sent: 23 November 2020 19:52
To: Prabhakar Mahadev Lad <prabhakar.mahadev-lad.rj@bp.renesas.com>
Cc: cip-dev@lists.cip-project.org; Nobuhiro Iwamatsu <nobuhiro1.iwamatsu@toshiba.co.jp>; Pavel Machek
<pavel@denx.de>; Biju Das <biju.das.jz@bp.renesas.com>
Subject: Re: [PATCH 4.19.y-cip 7/7] spi: add Renesas RPC-IF driver

Hi!

commit eb8d6d464a27850498dced21a8450e85d4a02009 upstream.

Add the SPI driver for the Renesas RPC-IF. It's the "front end" driver
using the "back end" APIs in the main driver to talk to the real hardware.
We only implement the 'spi-mem' interface -- there's no need to implement
the usual SPI driver methods...

Based on the original patch by Mason Yang <masonccyang@mxic.com.tw>.

Signed-off-by: Sergei Shtylyov <sergei.shtylyov@cogentembedded.com>
Link: https://lore.kernel.org/r/1ece0e6c-71af-f0f1-709e-571f4b0b4853@cogentembedded.com
Signed-off-by: Mark Brown <broonie@kernel.org>
Signed-off-by: Lad Prabhakar <prabhakar.mahadev-lad.rj@bp.renesas.com>
---
drivers/spi/Kconfig | 6 ++
drivers/spi/Makefile | 1 +
drivers/spi/spi-rpc-if.c | 216 +++++++++++++++++++++++++++++++++++++++
3 files changed, 223 insertions(+)
create mode 100644 drivers/spi/spi-rpc-if.c

diff --git a/drivers/spi/Kconfig b/drivers/spi/Kconfig
index 0a7fd56c1ed9..461315967f96 100644
--- a/drivers/spi/Kconfig
+++ b/drivers/spi/Kconfig
@@ -514,6 +514,12 @@ config SPI_RB4XX
help
SPI controller driver for the Mikrotik RB4xx series boards.

+config SPI_RPCIF
+ tristate "Renesas RPC-IF SPI driver"
+ depends on RENESAS_RPCIF
+ help
+ SPI driver for Renesas R-Car Gen3 RPC-IF.

Few lines here explaining the acronyms etc. would be nice.

+ error = spi_register_controller(ctlr);
+ if (error) {
+ dev_err(&pdev->dev, "spi_register_controller failed\n");
+ goto err_put_ctlr;
+ }
+ return 0;
+
+err_put_ctlr:
+ rpcif_disable_rpm(rpc);
+ spi_controller_put(ctlr);
+
+ return error;
+}

With just one user of the error exit, I'd avoid the goto.

+#ifdef CONFIG_PM_SLEEP
+static int rpcif_spi_suspend(struct device *dev)
+{
+ struct spi_controller *ctlr = dev_get_drvdata(dev);
+
+ return spi_controller_suspend(ctlr);
+}
+
+static int rpcif_spi_resume(struct device *dev)
+{
+ struct spi_controller *ctlr = dev_get_drvdata(dev);
+
+ return spi_controller_resume(ctlr);
+}
+
+static SIMPLE_DEV_PM_OPS(rpcif_spi_pm_ops, rpcif_spi_suspend, rpcif_spi_resume);
+#define DEV_PM_OPS (&rpcif_spi_pm_ops)
+#else
+#define DEV_PM_OPS NULL
+#endif
+
+static struct platform_driver rpcif_spi_driver = {
+ .probe = rpcif_spi_probe,
+ .remove = rpcif_spi_remove,
+ .driver = {
+ .name = "rpc-if-spi",
+ .pm = DEV_PM_OPS,
+ },
+};

Can you just add "__maybe_unused" annotation and avoid the ifdefs,
like atmel-quadspi.c does?

Best regards,
Pavel
--
DENX Software Engineering GmbH, Managing Director: Wolfgang Denk
HRB 165235 Munich, Office: Kirchenstr.5, D-82194 Groebenzell, Germany

-----Original Message-----
From: Pavel Machek <pavel@denx.de>
Sent: 23 November 2020 19:46
To: Prabhakar Mahadev Lad <prabhakar.mahadev-lad.rj@bp.renesas.com>
Cc: cip-dev@lists.cip-project.org; Nobuhiro Iwamatsu <nobuhiro1.iwamatsu@toshiba.co.jp>; Pavel Machek
<pavel@denx.de>; Biju Das <biju.das.jz@bp.renesas.com>
Subject: Re: [PATCH 4.19.y-cip 6/7] spi: spi-mem: Add a new API to support direct mapping

Hi!

commit aa167f3fed0c37e0e4c707d4331d827661f46644 upstream.

Most modern SPI controllers can directly map a SPI memory (or a portion
of the SPI memory) in the CPU address space. Most of the time this
brings significant performance improvements as it automates the whole
process of sending SPI memory operations every time a new region is
accessed.

This new API allows SPI memory drivers to create direct mappings and
then use them to access the memory instead of using
spi_mem_exec_op().

+ * Return: the amount of data read from the memory device or a negative error
+ * code. Note that the returned size might be smaller than @len, and the caller
+ * is responsible for calling spi_mem_dirmap_read() again when that happens.
+ */
+ssize_t spi_mem_dirmap_read(struct spi_mem_dirmap_desc *desc,
+ u64 offs, size_t len, void *buf)
+{
+ struct spi_controller *ctlr = desc->mem->spi->controller;
+ ssize_t ret;
+
+ if (desc->info.op_tmpl.data.dir != SPI_MEM_DATA_IN)
+ return -EINVAL;
+
+ if (!len)
+ return 0;
+
+ if (desc->nodirmap) {
+ ret = spi_mem_no_dirmap_read(desc, offs, len, buf);

I'd do return ... here.

+ } else if (ctlr->mem_ops && ctlr->mem_ops->dirmap_read) {
+ ret = spi_mem_access_start(desc->mem);
+ if (ret)
+ return ret;
+
+ ret = ctlr->mem_ops->dirmap_read(desc, offs, len, buf);
+
+ spi_mem_access_end(desc->mem);

and here.

+ } else {
+ ret = -ENOTSUPP;
+ }

To help with if/else nesting. spi_mem_dirmap_write could use same
treatment.

Best regards,
Pavel

--
DENX Software Engineering GmbH, Managing Director: Wolfgang Denk
HRB 165235 Munich, Office: Kirchenstr.5, D-82194 Groebenzell, Germany

-----Original Message-----
From: Pavel Machek <pavel@denx.de>
Sent: 23 November 2020 19:44
To: Prabhakar Mahadev Lad <prabhakar.mahadev-lad.rj@bp.renesas.com>
Cc: cip-dev@lists.cip-project.org; Nobuhiro Iwamatsu <nobuhiro1.iwamatsu@toshiba.co.jp>; Pavel Machek
<pavel@denx.de>; Biju Das <biju.das.jz@bp.renesas.com>
Subject: Re: [PATCH 4.19.y-cip 5/7] spi: spi-mem: Split spi_mem_exec_op() code

Hi!

From: Boris Brezillon <boris.brezillon@bootlin.com>

commit f86c24f4795303e4024bc113196de32782f6ccb5 upstream.

The logic surrounding the ->exec_op() call applies to direct mapping
accessors. Move this code to separate functions to avoid duplicating
code.

+++ b/drivers/spi/spi-mem.c
@@ -213,6 +213,44 @@ bool spi_mem_supports_op(struct spi_mem *mem, const struct spi_mem_op *op)
}
EXPORT_SYMBOL_GPL(spi_mem_supports_op);

+static int spi_mem_access_start(struct spi_mem *mem)
+{
+ struct spi_controller *ctlr = mem->spi->controller;

...

+ if (ctlr->auto_runtime_pm) {
+ int ret;
+
+ ret = pm_runtime_get_sync(ctlr->dev.parent);
+ if (ret < 0) {
+ dev_err(&ctlr->dev, "Failed to power device: %d\n",
+ ret);
+ return ret;
+ }

This misses pm_runtime_put() in the error case.

+ mutex_lock(&ctlr->bus_lock_mutex);
+ mutex_lock(&ctlr->io_mutex);

Plus hiding locking into function like this ... is quite
"interesting".

Best regards,
Pavel

--
DENX Software Engineering GmbH, Managing Director: Wolfgang Denk
HRB 165235 Munich, Office: Kirchenstr.5, D-82194 Groebenzell, Germany