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From: Eddie James <eajames@linux.ibm.com>
To: linux-fsi@lists.ozlabs.org
Cc: linux-kernel@vger.kernel.org, linux-i2c@vger.kernel.org,
        linux-spi@vger.kernel.org, broonie@kernel.org, andi.shyti@kernel.org,
        joel@jms.id.au, alistair@popple.id.au, jk@ozlabs.org,
        andrew@codeconstruct.com.au, linux-aspeed@lists.ozlabs.org,
        eajames@linux.ibm.com
Subject: [PATCH v3 34/40] fsi: core: Add master register read-only sysfs
Date: Thu, 16 May 2024 13:19:01 -0500
Message-Id: <20240516181907.3468796-35-eajames@linux.ibm.com>
In-Reply-To: <20240516181907.3468796-1-eajames@linux.ibm.com>
References: <20240516181907.3468796-1-eajames@linux.ibm.com>
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The master registers are commonly used for debugging or diagnosis so
provide them in sysfs files.

Signed-off-by: Eddie James <eajames@linux.ibm.com>
---
 drivers/fsi/fsi-core.c   | 144 +++++++++++++++++++++++++++++++++++++++
 drivers/fsi/fsi-master.h |   6 ++
 2 files changed, 150 insertions(+)

diff --git a/drivers/fsi/fsi-core.c b/drivers/fsi/fsi-core.c
index ae65d87d4b13e..096b26c6421f2 100644
--- a/drivers/fsi/fsi-core.c
+++ b/drivers/fsi/fsi-core.c
@@ -1392,6 +1392,141 @@ static ssize_t master_break_store(struct device *dev,
 
 static DEVICE_ATTR(break, 0200, NULL, master_break_store);
 
+struct fsi_master_attribute {
+	struct device_attribute attr;
+	int reg;
+};
+
+static ssize_t master_reg_show(struct device *dev, struct device_attribute *attr, char *buf)
+{
+	struct fsi_master_attribute *fattr = container_of(attr, struct fsi_master_attribute, attr);
+	struct fsi_master *master = to_fsi_master(dev);
+	unsigned int reg;
+	int rc;
+	
+	rc = regmap_read(master->map, fattr->reg, &reg);
+	if (rc)
+		return rc;
+
+	return sysfs_emit(buf, "%08x\n", reg);
+}
+
+static ssize_t master_reg_1bpp_show(struct device *dev, struct device_attribute *attr, char *buf)
+{
+	struct fsi_master_attribute *fattr = container_of(attr, struct fsi_master_attribute, attr);
+	struct fsi_master *master = to_fsi_master(dev);
+	unsigned int count = (master->n_links + 31) / 32;
+	unsigned int reg;
+	unsigned int i;
+	int len = 0;
+	int rc;
+	
+	for (i = 0; i < count; ++i) {
+		rc = regmap_read(master->map, fattr->reg + (i * 4), &reg);
+		if (rc)
+			return rc;
+
+		len += sysfs_emit_at(buf, len, "%08x\n", reg);
+	}
+
+	return len;
+}
+
+static ssize_t master_reg_4bpp_show(struct device *dev, struct device_attribute *attr, char *buf)
+{
+	struct fsi_master_attribute *fattr = container_of(attr, struct fsi_master_attribute, attr);
+	struct fsi_master *master = to_fsi_master(dev);
+	unsigned int count = (master->n_links + 7) / 8;
+	unsigned int reg;
+	unsigned int i;
+	int len = 0;
+	int rc;
+	
+	for (i = 0; i < count; ++i) {
+		rc = regmap_read(master->map, fattr->reg + (i * 4), &reg);
+		if (rc)
+			return rc;
+
+		len += sysfs_emit_at(buf, len, "%08x\n", reg);
+	}
+
+	return len;
+}
+
+static ssize_t master_reg_32bpp_show(struct device *dev, struct device_attribute *attr, char *buf)
+{
+	struct fsi_master_attribute *fattr = container_of(attr, struct fsi_master_attribute, attr);
+	struct fsi_master *master = to_fsi_master(dev);
+	unsigned int reg;
+	int len = 0;
+	int rc;
+	int i;
+	
+	for (i = 0; i < master->n_links; ++i) {
+		rc = regmap_read(master->map, fattr->reg + (i * 4), &reg);
+		if (rc)
+			return rc;
+
+		len += sysfs_emit_at(buf, len, "%08x\n", reg);
+	}
+
+	return len;
+}
+
+#define FSI_MASTER_ATTR(name, reg) \
+	struct fsi_master_attribute dev_attr_##name = { __ATTR(name, 0444, master_reg_show, NULL), reg }
+#define FSI_MASTER_ATTR_1BPP(name, reg) \
+	struct fsi_master_attribute dev_attr_##name = { __ATTR(name, 0444, master_reg_1bpp_show, NULL), reg }
+#define FSI_MASTER_ATTR_4BPP(name, reg) \
+	struct fsi_master_attribute dev_attr_##name = { __ATTR(name, 0444, master_reg_4bpp_show, NULL), reg }
+#define FSI_MASTER_ATTR_32BPP(name, reg) \
+	struct fsi_master_attribute dev_attr_##name = { __ATTR(name, 0444, master_reg_32bpp_show, NULL), reg }
+
+static FSI_MASTER_ATTR(mmode, FSI_MMODE);
+static FSI_MASTER_ATTR(mdlyr, FSI_MDLYR);
+static FSI_MASTER_ATTR_1BPP(mcrsp, FSI_MCRSP);
+static FSI_MASTER_ATTR_1BPP(menp, FSI_MENP0);
+static FSI_MASTER_ATTR_1BPP(mlevp, FSI_MLEVP0);
+static FSI_MASTER_ATTR_1BPP(mrefp, FSI_MREFP0);
+static FSI_MASTER_ATTR_1BPP(mhpmp, FSI_MHPMP0);
+static FSI_MASTER_ATTR_4BPP(msiep, FSI_MSIEP0);
+static FSI_MASTER_ATTR_1BPP(maesp, FSI_MAESP0);
+static FSI_MASTER_ATTR(maeb, FSI_MAEB);
+static FSI_MASTER_ATTR(mver, FSI_MVER);
+static FSI_MASTER_ATTR_1BPP(mbsyp, FSI_MBSYP0);
+static FSI_MASTER_ATTR_32BPP(mstap, FSI_MSTAP0);
+static FSI_MASTER_ATTR(mesrb, FSI_MESRB0);
+static FSI_MASTER_ATTR(mscsb, FSI_MSCSB0);
+static FSI_MASTER_ATTR(matrb, FSI_MATRB0);
+static FSI_MASTER_ATTR(mdtrb, FSI_MDTRB0);
+static FSI_MASTER_ATTR(mectrl, FSI_MECTRL);
+
+static struct attribute *master_mapped_attrs[] = {
+	&dev_attr_mmode.attr.attr,
+	&dev_attr_mdlyr.attr.attr,
+	&dev_attr_mcrsp.attr.attr,
+	&dev_attr_menp.attr.attr,
+	&dev_attr_mlevp.attr.attr,
+	&dev_attr_mrefp.attr.attr,
+	&dev_attr_mhpmp.attr.attr,
+	&dev_attr_msiep.attr.attr,
+	&dev_attr_maesp.attr.attr,
+	&dev_attr_maeb.attr.attr,
+	&dev_attr_mver.attr.attr,
+	&dev_attr_mbsyp.attr.attr,
+	&dev_attr_mstap.attr.attr,
+	&dev_attr_mesrb.attr.attr,
+	&dev_attr_mscsb.attr.attr,
+	&dev_attr_matrb.attr.attr,
+	&dev_attr_mdtrb.attr.attr,
+	&dev_attr_mectrl.attr.attr,
+	NULL
+};
+
+static const struct attribute_group master_mapped_group = {
+	.attrs = master_mapped_attrs,
+};
+
 static struct attribute *master_attrs[] = {
 	&dev_attr_break.attr,
 	&dev_attr_rescan.attr,
@@ -1665,6 +1800,12 @@ int fsi_master_register(struct fsi_master *master)
 	}
 out:
 	mutex_unlock(&master->scan_lock);
+
+	if (!rc && master->map) {
+		if (!sysfs_create_group(&master->dev.kobj, &master_mapped_group))
+			master->groups = true;
+	}
+
 	return rc;
 }
 EXPORT_SYMBOL_GPL(fsi_master_register);
@@ -1675,6 +1816,9 @@ void fsi_master_unregister(struct fsi_master *master)
 
 	trace_fsi_master_unregister(master);
 
+	if (master->groups)
+		sysfs_remove_group(&master->dev.kobj, &master_mapped_group);
+
 	mutex_lock(&master->scan_lock);
 	fsi_master_unscan(master);
 	master->n_links = 0;
diff --git a/drivers/fsi/fsi-master.h b/drivers/fsi/fsi-master.h
index 2104902091e05..1fa101a477899 100644
--- a/drivers/fsi/fsi-master.h
+++ b/drivers/fsi/fsi-master.h
@@ -12,6 +12,7 @@
 #include <linux/device.h>
 #include <linux/irq.h>
 #include <linux/mutex.h>
+#include <linux/sysfs.h>
 
 /*
  * Master registers
@@ -27,12 +28,16 @@
 #define FSI_MENP0		0x10		/* R/W: enable */
 #define FSI_MLEVP0		0x18		/* R: plug detect */
 #define FSI_MSENP0		0x18		/* S: Set enable */
+#define FSI_MREFP0		0x20		/* R: Plug reference */
 #define FSI_MCENP0		0x20		/* C: Clear enable */
+#define FSI_MHPMP0		0x28		/* R: Plug monitor */
 #define FSI_MSIEP0		0x30		/* R/W: interrupt enable */
+#define FSI_MAESP0		0x50		/* R: Any error port */
 #define FSI_MSSIEP0		0x50		/* S: Set interrupt enable */
 #define FSI_MCSIEP0		0x70		/* C: Clear interrupt enable */
 #define FSI_MAEB		0x70		/* R: Error address */
 #define FSI_MVER		0x74		/* R: master version/type */
+#define FSI_MBSYP0		0x78		/* R: Port busy */
 #define FSI_MSTAP0		0xd0		/* R: Port status */
 #define FSI_MRESP0		0xd0		/* W: Port reset */
 #define FSI_MESRB0		0x1d0		/* R: Master error status */
@@ -151,6 +156,7 @@ struct fsi_master {
 	int		(*link_config)(struct fsi_master *, int link,
 				       u8 t_send_delay, u8 t_echo_delay);
 	u8		remote_interrupt_status;
+	bool		groups;
 };
 
 #define to_fsi_master(d) container_of(d, struct fsi_master, dev)
-- 
2.39.3