diff mbox series

[07/23] wfx: add bus_sdio.c

Message ID 20201012104648.985256-8-Jerome.Pouiller@silabs.com
State Superseded
Headers show
Series wfx: get out from the staging area | expand

Commit Message

Jérôme Pouiller Oct. 12, 2020, 10:46 a.m. UTC
From: Jérôme Pouiller <jerome.pouiller@silabs.com>

Signed-off-by: Jérôme Pouiller <jerome.pouiller@silabs.com>
---
 drivers/net/wireless/silabs/wfx/bus_sdio.c | 269 +++++++++++++++++++++
 1 file changed, 269 insertions(+)
 create mode 100644 drivers/net/wireless/silabs/wfx/bus_sdio.c

Comments

Pali Rohár Oct. 13, 2020, 8:11 p.m. UTC | #1
Hello!

On Monday 12 October 2020 12:46:32 Jerome Pouiller wrote:
> +#define SDIO_VENDOR_ID_SILABS        0x0000
> +#define SDIO_DEVICE_ID_SILABS_WF200  0x1000
> +static const struct sdio_device_id wfx_sdio_ids[] = {
> +	{ SDIO_DEVICE(SDIO_VENDOR_ID_SILABS, SDIO_DEVICE_ID_SILABS_WF200) },

Please move ids into common include file include/linux/mmc/sdio_ids.h
where are all SDIO ids. Now all drivers have ids defined in that file.

> +	// FIXME: ignore VID/PID and only rely on device tree
> +	// { SDIO_DEVICE(SDIO_ANY_ID, SDIO_ANY_ID) },

What is the reason for ignoring vendor and device ids?

> +	{ },
> +};
> +MODULE_DEVICE_TABLE(sdio, wfx_sdio_ids);
> +
> +struct sdio_driver wfx_sdio_driver = {
> +	.name = "wfx-sdio",
> +	.id_table = wfx_sdio_ids,
> +	.probe = wfx_sdio_probe,
> +	.remove = wfx_sdio_remove,
> +	.drv = {
> +		.owner = THIS_MODULE,
> +		.of_match_table = wfx_sdio_of_match,
> +	}
> +};
> -- 
> 2.28.0
>
Jérôme Pouiller Oct. 14, 2020, 11:52 a.m. UTC | #2
Hello Pali,

On Tuesday 13 October 2020 22:11:56 CEST Pali Rohár wrote:
> Hello!

> 

> On Monday 12 October 2020 12:46:32 Jerome Pouiller wrote:

> > +#define SDIO_VENDOR_ID_SILABS        0x0000

> > +#define SDIO_DEVICE_ID_SILABS_WF200  0x1000

> > +static const struct sdio_device_id wfx_sdio_ids[] = {

> > +     { SDIO_DEVICE(SDIO_VENDOR_ID_SILABS, SDIO_DEVICE_ID_SILABS_WF200) },

> 

> Please move ids into common include file include/linux/mmc/sdio_ids.h

> where are all SDIO ids. Now all drivers have ids defined in that file.

> 

> > +     // FIXME: ignore VID/PID and only rely on device tree

> > +     // { SDIO_DEVICE(SDIO_ANY_ID, SDIO_ANY_ID) },

> 

> What is the reason for ignoring vendor and device ids?


The device has a particularity, its VID/PID is 0000:1000 (as you can see
above). This value is weird. The risk of collision with another device is
high.

So, maybe the device should be probed only if it appears in the DT. Since
WF200 targets embedded platforms, I don't think it is a problem to rely on
DT. You will find another FIXME further in the code about that:

+               dev_warn(&func->dev,
+                        "device is not declared in DT, features will be limited\n");
+               // FIXME: ignore VID/PID and only rely on device tree
+               // return -ENODEV;

However, it wouldn't be usual way to manage SDIO devices (and it is the
reason why the code is commented out).

Anyway, if we choose to rely on the DT, should we also check the VID/PID?

Personally, I am in favor to probe the device only if VID/PID match and if
a DT node is found, even if it is not the usual way.

-- 
Jérôme Pouiller
diff mbox series

Patch

diff --git a/drivers/net/wireless/silabs/wfx/bus_sdio.c b/drivers/net/wireless/silabs/wfx/bus_sdio.c
new file mode 100644
index 000000000000..e06d7e1ebe9c
--- /dev/null
+++ b/drivers/net/wireless/silabs/wfx/bus_sdio.c
@@ -0,0 +1,269 @@ 
+// SPDX-License-Identifier: GPL-2.0-only
+/*
+ * SDIO interface.
+ *
+ * Copyright (c) 2017-2020, Silicon Laboratories, Inc.
+ * Copyright (c) 2010, ST-Ericsson
+ */
+#include <linux/module.h>
+#include <linux/mmc/sdio.h>
+#include <linux/mmc/sdio_func.h>
+#include <linux/mmc/card.h>
+#include <linux/interrupt.h>
+#include <linux/of_irq.h>
+#include <linux/irq.h>
+
+#include "bus.h"
+#include "wfx.h"
+#include "hwio.h"
+#include "main.h"
+#include "bh.h"
+
+static const struct wfx_platform_data wfx_sdio_pdata = {
+	.file_fw = "wfm_wf200",
+	.file_pds = "wf200.pds",
+};
+
+struct wfx_sdio_priv {
+	struct sdio_func *func;
+	struct wfx_dev *core;
+	u8 buf_id_tx;
+	u8 buf_id_rx;
+	int of_irq;
+};
+
+static int wfx_sdio_copy_from_io(void *priv, unsigned int reg_id,
+				 void *dst, size_t count)
+{
+	struct wfx_sdio_priv *bus = priv;
+	unsigned int sdio_addr = reg_id << 2;
+	int ret;
+
+	WARN(reg_id > 7, "chip only has 7 registers");
+	WARN(((uintptr_t)dst) & 3, "unaligned buffer size");
+	WARN(count & 3, "unaligned buffer address");
+
+	/* Use queue mode buffers */
+	if (reg_id == WFX_REG_IN_OUT_QUEUE)
+		sdio_addr |= (bus->buf_id_rx + 1) << 7;
+	ret = sdio_memcpy_fromio(bus->func, dst, sdio_addr, count);
+	if (!ret && reg_id == WFX_REG_IN_OUT_QUEUE)
+		bus->buf_id_rx = (bus->buf_id_rx + 1) % 4;
+
+	return ret;
+}
+
+static int wfx_sdio_copy_to_io(void *priv, unsigned int reg_id,
+			       const void *src, size_t count)
+{
+	struct wfx_sdio_priv *bus = priv;
+	unsigned int sdio_addr = reg_id << 2;
+	int ret;
+
+	WARN(reg_id > 7, "chip only has 7 registers");
+	WARN(((uintptr_t)src) & 3, "unaligned buffer size");
+	WARN(count & 3, "unaligned buffer address");
+
+	/* Use queue mode buffers */
+	if (reg_id == WFX_REG_IN_OUT_QUEUE)
+		sdio_addr |= bus->buf_id_tx << 7;
+	// FIXME: discards 'const' qualifier for src
+	ret = sdio_memcpy_toio(bus->func, sdio_addr, (void *)src, count);
+	if (!ret && reg_id == WFX_REG_IN_OUT_QUEUE)
+		bus->buf_id_tx = (bus->buf_id_tx + 1) % 32;
+
+	return ret;
+}
+
+static void wfx_sdio_lock(void *priv)
+{
+	struct wfx_sdio_priv *bus = priv;
+
+	sdio_claim_host(bus->func);
+}
+
+static void wfx_sdio_unlock(void *priv)
+{
+	struct wfx_sdio_priv *bus = priv;
+
+	sdio_release_host(bus->func);
+}
+
+static void wfx_sdio_irq_handler(struct sdio_func *func)
+{
+	struct wfx_sdio_priv *bus = sdio_get_drvdata(func);
+
+	wfx_bh_request_rx(bus->core);
+}
+
+static irqreturn_t wfx_sdio_irq_handler_ext(int irq, void *priv)
+{
+	struct wfx_sdio_priv *bus = priv;
+
+	sdio_claim_host(bus->func);
+	wfx_bh_request_rx(bus->core);
+	sdio_release_host(bus->func);
+	return IRQ_HANDLED;
+}
+
+static int wfx_sdio_irq_subscribe(void *priv)
+{
+	struct wfx_sdio_priv *bus = priv;
+	u32 flags;
+	int ret;
+	u8 cccr;
+
+	if (!bus->of_irq) {
+		sdio_claim_host(bus->func);
+		ret = sdio_claim_irq(bus->func, wfx_sdio_irq_handler);
+		sdio_release_host(bus->func);
+		return ret;
+	}
+
+	sdio_claim_host(bus->func);
+	cccr = sdio_f0_readb(bus->func, SDIO_CCCR_IENx, NULL);
+	cccr |= BIT(0);
+	cccr |= BIT(bus->func->num);
+	sdio_f0_writeb(bus->func, cccr, SDIO_CCCR_IENx, NULL);
+	sdio_release_host(bus->func);
+	flags = irq_get_trigger_type(bus->of_irq);
+	if (!flags)
+		flags = IRQF_TRIGGER_HIGH;
+	flags |= IRQF_ONESHOT;
+	return devm_request_threaded_irq(&bus->func->dev, bus->of_irq, NULL,
+					 wfx_sdio_irq_handler_ext, flags,
+					 "wfx", bus);
+}
+
+static int wfx_sdio_irq_unsubscribe(void *priv)
+{
+	struct wfx_sdio_priv *bus = priv;
+	int ret;
+
+	if (bus->of_irq)
+		devm_free_irq(&bus->func->dev, bus->of_irq, bus);
+	sdio_claim_host(bus->func);
+	ret = sdio_release_irq(bus->func);
+	sdio_release_host(bus->func);
+	return ret;
+}
+
+static size_t wfx_sdio_align_size(void *priv, size_t size)
+{
+	struct wfx_sdio_priv *bus = priv;
+
+	return sdio_align_size(bus->func, size);
+}
+
+static const struct hwbus_ops wfx_sdio_hwbus_ops = {
+	.copy_from_io = wfx_sdio_copy_from_io,
+	.copy_to_io = wfx_sdio_copy_to_io,
+	.irq_subscribe = wfx_sdio_irq_subscribe,
+	.irq_unsubscribe = wfx_sdio_irq_unsubscribe,
+	.lock			= wfx_sdio_lock,
+	.unlock			= wfx_sdio_unlock,
+	.align_size		= wfx_sdio_align_size,
+};
+
+static const struct of_device_id wfx_sdio_of_match[] = {
+	{ .compatible = "silabs,wfx-sdio" },
+	{ .compatible = "silabs,wf200" },
+	{ },
+};
+MODULE_DEVICE_TABLE(of, wfx_sdio_of_match);
+
+static int wfx_sdio_probe(struct sdio_func *func,
+			  const struct sdio_device_id *id)
+{
+	struct device_node *np = func->dev.of_node;
+	struct wfx_sdio_priv *bus;
+	int ret;
+
+	if (func->num != 1) {
+		dev_err(&func->dev, "SDIO function number is %d while it should always be 1 (unsupported chip?)\n",
+			func->num);
+		return -ENODEV;
+	}
+
+	bus = devm_kzalloc(&func->dev, sizeof(*bus), GFP_KERNEL);
+	if (!bus)
+		return -ENOMEM;
+
+	if (np) {
+		if (!of_match_node(wfx_sdio_of_match, np)) {
+			dev_warn(&func->dev, "no compatible device found in DT\n");
+			return -ENODEV;
+		}
+		bus->of_irq = irq_of_parse_and_map(np, 0);
+	} else {
+		dev_warn(&func->dev,
+			 "device is not declared in DT, features will be limited\n");
+		// FIXME: ignore VID/PID and only rely on device tree
+		// return -ENODEV;
+	}
+
+	bus->func = func;
+	sdio_set_drvdata(func, bus);
+	func->card->quirks |= MMC_QUIRK_LENIENT_FN0 |
+			      MMC_QUIRK_BLKSZ_FOR_BYTE_MODE |
+			      MMC_QUIRK_BROKEN_BYTE_MODE_512;
+
+	sdio_claim_host(func);
+	ret = sdio_enable_func(func);
+	// Block of 64 bytes is more efficient than 512B for frame sizes < 4k
+	sdio_set_block_size(func, 64);
+	sdio_release_host(func);
+	if (ret)
+		goto err0;
+
+	bus->core = wfx_init_common(&func->dev, &wfx_sdio_pdata,
+				    &wfx_sdio_hwbus_ops, bus);
+	if (!bus->core) {
+		ret = -EIO;
+		goto err1;
+	}
+
+	ret = wfx_probe(bus->core);
+	if (ret)
+		goto err1;
+
+	return 0;
+
+err1:
+	sdio_claim_host(func);
+	sdio_disable_func(func);
+	sdio_release_host(func);
+err0:
+	return ret;
+}
+
+static void wfx_sdio_remove(struct sdio_func *func)
+{
+	struct wfx_sdio_priv *bus = sdio_get_drvdata(func);
+
+	wfx_release(bus->core);
+	sdio_claim_host(func);
+	sdio_disable_func(func);
+	sdio_release_host(func);
+}
+
+#define SDIO_VENDOR_ID_SILABS        0x0000
+#define SDIO_DEVICE_ID_SILABS_WF200  0x1000
+static const struct sdio_device_id wfx_sdio_ids[] = {
+	{ SDIO_DEVICE(SDIO_VENDOR_ID_SILABS, SDIO_DEVICE_ID_SILABS_WF200) },
+	// FIXME: ignore VID/PID and only rely on device tree
+	// { SDIO_DEVICE(SDIO_ANY_ID, SDIO_ANY_ID) },
+	{ },
+};
+MODULE_DEVICE_TABLE(sdio, wfx_sdio_ids);
+
+struct sdio_driver wfx_sdio_driver = {
+	.name = "wfx-sdio",
+	.id_table = wfx_sdio_ids,
+	.probe = wfx_sdio_probe,
+	.remove = wfx_sdio_remove,
+	.drv = {
+		.owner = THIS_MODULE,
+		.of_match_table = wfx_sdio_of_match,
+	}
+};