Re: [RFC PATCH v2 3/3] nvmem: zynqmp: Added zynqmp nvmem firmware driver

From: Srinivas Kandagatla
Date: Sun Sep 16 2018 - 10:10:45 EST


Few minor Nits...

I remember asking about this in the last review!

On 04/09/18 10:52, Nava kishore Manne wrote:
This patch adds zynqmp nvmem firmware driver to access the
SoC revision information from the hardware register.

Signed-off-by: Nava kishore Manne <nava.manne@xxxxxxxxxx>
---
diff --git a/drivers/nvmem/zynqmp_nvmem.c b/drivers/nvmem/zynqmp_nvmem.c
new file mode 100644
index 0000000..e377900
--- /dev/null
+++ b/drivers/nvmem/zynqmp_nvmem.c
@@ -0,0 +1,84 @@
+// SPDX-License-Identifier: GPL-2.0+
+/*
+ * Copyright (C) 2018 Xilinx, Inc.
+ */
+
+#include <linux/module.h>
+#include <linux/nvmem-provider.h>
+#include <linux/of.h>
+#include <linux/platform_device.h>
+#include <linux/firmware/xlnx-zynqmp.h>
+
+#define SILICON_REVISION_MASK 0xF
+
+static int zynqmp_nvmem_read(void *context, unsigned int offset,
+ void *val, size_t bytes)
+{
+ int ret;
+ int idcode, version;
+ const struct zynqmp_eemi_ops *eemi_ops = zynqmp_pm_get_eemi_ops();
+
+ if (!eemi_ops || !eemi_ops->get_chipid)
+ return -ENXIO;
+
+ ret = eemi_ops->get_chipid(&idcode, &version);
+ if (ret < 0)
+ return ret;
+
+ pr_debug("Read chipid val %x %x\n", idcode, version);
+ *(int *)val = version & SILICON_REVISION_MASK;

Use dev_dbg here.
+
+ return 0;
+}
+
+static struct nvmem_config econfig = {
+ .name = "zynqmp-nvmem",
+ .owner = THIS_MODULE,
+ .word_size = 1,
+ .size = 1,
+ .read_only = true,
+};
+
+static const struct of_device_id zynqmp_nvmem_match[] = {
+ { .compatible = "xlnx,zynqmp-nvmem-fw", },
+ { /* sentinel */ },
+};
+MODULE_DEVICE_TABLE(of, zynqmp_nvmem_match);
+
+static int zynqmp_nvmem_probe(struct platform_device *pdev)
+{
+ struct nvmem_device *nvmem;
+
+ econfig.dev = &pdev->dev;
+ econfig.reg_read = zynqmp_nvmem_read;
+
+ nvmem = nvmem_register(&econfig);
You can use devm_ variant and remove the zynqmp_nvmem_remove() totally

+ if (IS_ERR(nvmem))
+ return PTR_ERR(nvmem);
+
+ platform_set_drvdata(pdev, nvmem);
+
+ return 0;
+}
+
+static int zynqmp_nvmem_remove(struct platform_device *pdev)
+{
+ struct nvmem_device *nvmem = platform_get_drvdata(pdev);
+
+ return nvmem_unregister(nvmem);
+}
+